With clearos horizontal or slightly upward is the only way I get enough juice at the coil. With the vision I'm finding I just give it a sec upside down and I can vape a few drags until the gurgling stops. It gurgles a bit but it keeps the coil absolutely wet and give great flavor without any heat related flavor issues. It isn't perfect and if anything allows too much juice to the coil, resulting in a lot of un vaped juice getting between mouthpiece and plugs. However the plug has a cone shape to it and runs juice back to the coil which helps. The mouthpiece get juice condensation in the little gap at the top and eventually will give a little spit. All in all it is a very nice vape. I haven't touched a bottle since I filled it this morning and have a quarter tank left so it's going well. There have been a couple draws where the flavor changed a little but a quick flip and all is well. So 90% of hits are perfect flavor and the other 10% are still good just a little off. I'm liking a lot!