Ugh, so many options and I'm getting confused and frustrated. Dead links on the site to various products...
After giving my vape choices another thought, I've decided that I may want a TV product. I like the Alpha Ultralight. The size specifically. I'd like to get back into the e-cig scene and have the option of using concentrates. I also want to be able to do this stealthily, not because I care about anyone close to me knowing, but because sometimes shit happens and I get a bout of nausea while I'm out running errands and I don't want to mess around with flower. Sometimes I just need a quick couple hits of oil (or at least something stronger) because cannabis doesn't sedate me nearly as bad as the promethazine pills I have for nausea.
It's not you, it's not easy to figure out exactly what each piece is used for, and the TV site is often very confusing and frustrating. You've come to the right place though, and I'll try to help.
Three parts make up what you're looking for. The power part, the vaporizer part, and the mouthpiece. You want something small, to be used for e-cig juice and concentrates. Not for herbals and not for hash.
For the battery part, keeping in mind you want small, you have two choices. The Alpha Ultra and the Alpha UltraLite. I highly recommend you look at the pictures on the ThermoVape web site, and decide if the Ultra is
really too big. There are pictures of both with a cigarette next to them to get a good idea of the size. The Ultra uses an "AA" size battery and the UltraLite uses an "AAA" size battery. You will get
much more life (number of puffs before needing to recharge the battery) with the Ultra. Two or three times more, at least. If you really really want the tiny UltraLite, just keep in mind you're going to be swapping out batteries frequently. That said, I own an UltraLite, and love it, and it's really tiny. I only use it for Pure Gold oil though, and haven't tried it with anything else (except E-Juice, which I didn't get along with, but which worked just fine!). Some concentrates other than Pure Gold (or a similar very pure oil) require much more heating before they melt and vaporize. Waxes may require you to poke them around to get them positioned over the ceramic insert before they melt and vaporize, which will also wind up eating your battery. Again, I highly recommend the Ultra over the UltraLite unless you really really want the smaller size (it's only a little smaller), and you're really really aware that you're sacrificing battery life. For either the Ultra or UltraLite, you also have to get some batteries that fit it, and a charger to charge them. With an Ultra, two batteries should be fine (at least to start), and I would recommend four batteries if you decide on the UltraLite. The charger is the same for either.
For the mouthpiece part, you have a bunch of similar choices. You have short mouthpieces in white and black Delrin and white PTFE (Teflon). You have a medium length black Delrin mouthpiece with a restricted flow. And you have extended (long) mouthpieces in black and white Delrin. All of the mouthpieces can be fitted with a "UFO" in the vaporizer end, which allows airflow, but blocks particulate matter. The UFO isn't really needed with a device used for concentrates and E-Juice, but it's useful when vaping herb. I have all the above, and 99% of the time I just use the short white PTFE mouthpiece or the medium restricted draw mouthpiece. You do have to be aware of the vaporizer cylinder when you use a short mouthpiece, as it's easy to take too much of the short mouthpiece into your mouth and consequently burn your lips on the end of the hot vaporizer... This is probably the "section" to mention the DART, which really describes a mouthpiece extension more than a vaporizer variation. The DART mouthpiece extension is an extra piece that looks like a UFO on steroids. The bottom of the DART fits into the top of the vaporizer core in the same place as a mouthpiece would, and the mouthpiece fits into the top of the DART. There is a cone shaped "dart" that comes out of the bottom of the UFO part, and extends down into the vaporizer cylinder to just above the ceramic insert. It's purpose (I think) is to help all the vapor that would condense in the vaporizer tube condense on it, and drip back onto the ceramic. The DART tip can also be used to "dip" into oil, or to "pick up" a bit of wax, and to then have it be positioned perfectly for the heating core to cause it to melt and drip on the ceramic insert. I have two DART mouthpieces and have never used either. So I must let others here explain the advantages and proper usage of the DART mouthpiece extension.
The vaporizer part is probably the most confusing. Thermovape makes both LV/LR (3.x volt) and SV (standard voltage, 6v) vaporizers. In your case (Ultra or UltraLite), you want a low voltage (LV) or low resistance (LR) vaporizer. The LV Revolution, LV DART, and LR AVA vaporizers are all electrically identical, and are all suitable for your needs. Here's what the differences are. The LV DART and LR AVA cores are identical except for the engraving on the side. The difference is that the LV DART comes with a DART mouthpiece extension and the LR AVA comes with a standard mouthpiece. The Revolution is a little different in the construction of the metal cylinder. Instead of a solid tube that the mouthpiece goes into, there is a cutout low down on one side, and an outer rotating metal shell that when rotated can expose and cover the cutout. This is to facilitate you putting your concentrate directly on the ceramic plate from the side of the vaporizer cylinder rather than dropping it in from the top where the mouthpiece goes. I don't own a Revolution as I only use oil, and there are problems with oil leaking out of the Revo cutout, and it generally becoming a sticky mess. Again I will rely on others here to give you their experiences with the Revo core versus the DART core. For your needs, I think the DART or AVA core might be the correct choice.
E-cig: UltraLite paired with the AVA-LR that comes with the "Tru-Flow Drip Tip" which I assume is where I put the drops of juice in. So... the Alpha UltraLite page, the $90 one is for the body and batteries, right? Then if I want e-cig ability, what am I supposed to get? The "AVA-LR Low Resistance - USA Made Atomizer" ? That's another $40.Do I have to get the AVA from TV or can I get a cheaper one that would work with this (without an adapter) ? Then if I want to get some concentrates (BHO) going, I go for the $55 "ThermoVape Revolution LV (Low Voltage) Vaporizer Cartridge" right? $140 just for oil when an Omicron is available for $120 doesn't make sense...
You need the battery parts, one core, and one mouthpiece. With two batteries and a charger the Ultra body is $100 and the UltraLite body is $90. The LV AVA core with a standard mouthpiece is $40. If you want separate vaporizer cores for your E-Juice and your concentrates, you will have to buy a second core. An extra core without mouthpiece is $35 (or $40 if you want it with a second mouthpiece, or $45 if you want it with a DART extension). If you don't mind adding a couple of drops of thc oil to a core that you also use for E-Juice you can get away with just one core.
It's really late now, and I'm passing out, so I will have to leave for tomorrow going to the ThermoVape web site and getting you links to each of the items you want. You should be aware that ThermoVape bends over backwards to let you order exactly what you need. Their web site doesn't always make it easy to figure out how.