So many stems for the AA (and solo) are what make it so great. I have probably every one (all the stock stuff, PV stuff, Joda, Ed's TNT - did I miss one?) Truth is I'll go through phases of loving a particular stem, then wind up back at one of the stocks. I'll give you a brief rating of what
I think of each stem, but remember, it's based on my ability to get results, maybe others might be
more or less skilled.
STOCK STUFF
Tip - tip rocks for pulling harder. Resistance is greater through the hole, but the pressure must go up as your lungs suck through a tiny port. I can work this bad boy, with breath, tongue in front of the hole. I can make the vape seem like warm velvet swimming across the top of my tongue. Taste top notch... I can lift the stem a hair off the bottom to increase flow, sometimes I'll spin, sometime stir. With the new drying technique, I can usually start at blue and kill it before the second green session. Super stealth.
ps - I finally got one of those tip stems that water condenses in, so strange that only one does it
No Tip
Almost the same but takes a bit more skill with the tongue. You can produce almost the same effect as the tiny hole in the tipped stem, but using your tongue as a 'flap' over the stem opening gives you lots of control (like playing the flute). Sometimes the feel of all glass is what I want, not the concentrated opening of the plastic tip (which has no taste BTW).
Bent Stem
I love the bent stem. Definitely gets a bit cooler as it travels around that 45 degree angle. I love to be lying down, AA standing up on my chest, bent stem right at mouth level. It might swivel a bit (on my smaller ones???), but no big deal. I have a couple that are quite tight. Smooth, satisfying, a bit cooler. Love to lean the stem from side to side to play with the seal and suction (you can actually do this will all the stems to a degree).
Long Straight
Just like the bent but straight. Maybe the angle on the bent cools a hair more, maybe my tongue hits it different and makes it seem that way. But I like the long stems sometimes when stealth isn't important.
PlanetVape
Regular vs Shorty / 30% smaller bowl. All use screens (stock stuff does not). My favorite is the vortex shorty.
Vortex - stems narrows to a smaller diameter just above the bowl.
Turbo - stem is wide open all the way through
They also have a bent, and I think stubby's (I don't have as stubby).
On all PV stuff, you have the air vents (like Ed and Joda) to increase air flow. Does this reduce vapor density? I guess it has to, it is mixing air into your vape. Still tastes great, cooler, smooth, but not as dense.
Ed
Awesome if you like wood. Super stealth on the short guys. I love the short one in my AA for on the go. Gotta bump up a hair in temp to overcome the SS. You can pick up a wood flavor here, you might like that, you might not.
Joda
Tight, but nice. I finally got my Joda to seat nicely in one of my AA's last night, great thick vapor. I'll have more to report about this little gem. The glass is thicker, and I guess holds the heat, but the experience changes, still learning it.
I'm sure I'm missing something, and this is not bible, just my experience. You may have different results with different stems based on so many factors. Usually, as
@OF always points out, I wind up back with the stock stuff (which is also the easiest to clean and maintain - no screens).
As a side note, not sure if my AA buddies saw this!