Really?
So you rarely actually use the Variable Voltage function?
Not sure what you mean by "rarely aactually use the variable voltage function"....
Generally, I would put a MAP tank on my ProVari in the morning before leaving home, fill it with one juice or another, then be gone all day, taking the ProVari with MAP Tank with me.
If I have a specific Map tank on my ProVari, why would I need to constantly change the voltage? I find the voltage that I like best with THAT combination of carto and juice, and basically leave it at that setting. What's great about the ProVari is you don't get different voltages as the battery loses charge... set it to, say, 4.2 and it stays at 4.2 all day, until the battery finally dies.
I'm now using Vision Extreme's. Again, I put a Vision on my PV, fill it, set it and forget it.
I do change voltage depending the the resistance on the atty/carto I'm using, and some juice tastes better at higher or lower settings, but again, generally, I set it and leave home and don't really need to change the voltage until or unless I change my carto and or juice.
By the way... we're talking SECONDS to change the voltage. Guess I'm a slacker, but so far, in the entire past year, I have NEVER not had the time to change the voltage, nor do I find it a hassle. Not saying LavaTube's button setup may not be better then the ProVari, just that I haven't had an issue with six or eight button clicks.