I own/have owned several whip style vaporizers (Vapezilla, SSV, Vapor Brothers, Easy Vape and Hot Box). So I have some background I can give.
Personally, I like my Hot Box. BUT, I think the reason I like it is because of the type of vaporist I am (style of drawing and use), NOT because I think it is a better vaporizer than any others I have - it's different in a way that works for me. I firmly believe in this site's slogan "there is no 'best' vape". But I can give you some basic differences that I have noted that might help you decide if it would work for you based on how you think you will use it.
External Heat - the outside of the HB gets HOT - very hot. I haven't found this to be an issue myself because I sit down to use it and then turn it off/unplug it. It does cool down quickly. While in use, I do not leave it unattended, nor does the manufacturer recommend that (based on a comment in an email I got from them about their aromatherapy bowl). It sits on a 6x6 tile I bought at Home Depot for $.88 and it isn't an issue. However, it you think it could be left on or would want to leave it on in between uses, then it wouldn't be a good choice for you.
The VB gets hot on the top of the unit after about 15 minutes, but not too hot to handle. The rest of the unit stays cool to the touch. I have left it on all day, putting the aromatherapy bowl on between uses and it didn't get hot beyond the top and that wasn't very hot at all.
The SSV stays cool. I have left it on for more than 24 hours and it was not much more than mildly warm to the touch - and that was only in the top inch or so of the unit, the rest of it was completely cool. I have the least heat concerns with the SSV.
Learning Curve: One of the reasons I really like the HB is because, for me, there was no learning curve. I am someone who breaths/draws quickly while vaporizing. It is my default. The speed at which I draw has been a negative issue with other vapes because I have to continually tell myself to slow down or I don't get vapor (can be frustrating) , but my style of hitting appears to be more of a benefit to the use of the HB - I always get vapor, with just how I normally draw. On the other hand - the HB is a set temperature vape, so all heat control is done solely by drawing speed. If you go too slow you will burn your load - every time - black! Not fun! I have read reviews where this is a big learning curve for some - They have to learn to draw more quickly and spend a week or so burning things before they get it down. That's a big drawback for some.
The only learning curve on my VB was finding the spot on the dial that worked. It was pretty much connect and go once I found it. And I think it was what was recommended on their website. I can get vapor from the VB drawing slow or drawing fast. I have darkly-browned some herb with the VB, but I personally have never burned anything in it. I have read it can easily be done though.
I had the most learning curve with the SSV. It doesn't seem to like the fast draw and if I don't pay attention, I'll default to my quick speed and not have luck with the SSV. While there are many, many things I like about the SSV, on days when I am not in the mood or are rushed, I find the SSV to be aggravating. For me, it has been the most "finicky" when it comes to technique. I have read many reviews though where that is not the case at all - that for the person there is little or no learning curve. Go figure.
Taste: Each unit produces good tasting vapor, but of the three, the order in which I think they produce cleaner tasting vapor are: 1st) SSV, 2) HB, 3) VB.
Amount of herb: All of the units will produce vapor with small amount (PD size), however, I have found their production of hits and vapor on those amounts to be best in the following order: 1) HB, 2) SSV, 3) VB. I should also note that I have had more luck getting vapor out of low grade weed with the HB than I have with the other two.
Angle of heating unit: the VB goes up and that is kind of a pain. Herb can fall on the heating unit. I have read many people get over the angle thing by putting something under the end to level it or turning it on its side. I use the screen sandwich method, so I've adapted, but the angle goes in the minus column for me. The SSV is a down angle. It is easy to use and you don't have herb falling on the heater, it is a good design and a plus. The HB is basically level, so you don't have green falling on the heater an it is easy to use - a plus side too.
Aromatherapy: I don't have the top for the SSV yet, just ordered it this last weekend, so I don't know on that. The VB came with a great bulb and it does a good job of diffusing scents. I bought the basic HB so I had to pay an additional $25 for the aromatherapy bulb for it and it is not a good diffuser! If you overfill it, it will boil and spit. I don't use it for scent diffusing!! I do however use it for stealth purposes and it works really well for that.
Price: I got a great deal on my SSV at a local head shop and I've bought additional glass for it, so I've got about $240 into it with the upgrades. I bought the coffee colored VB which was $169. I bought the HB off ebay on a "make an offer" where the dealer accepted a $115 offer and I then spent another $25 on the bulb.
I like them all and I use them all at different times and when I'm in different moods. And I would recommend them all depending on what that person is looking for. I think they all have positives and all have negatives. I think you should think about those and how you are going to vape and them make a decision.
But whips are far from stealth. 
She normally knocks but not this time! I spun around in an attempt to hide the whip and sprayed Spice Gold all over the bench top. 
If I had of been loading a PD tube it would have been much easier to hide ... and if I lost a PD bowl full of herbs ... so the fuck what 
. Or, for that price you could also get a MyrtleZap (MZ), but that is a very different type of vape. I'd suggest reading through a few of the product-specific threads here. Lots of good info to help you choose. 
