My 2c worth...reposted from another thread on the same issue.
Super value VV - The Madvapes VV box...for $35, it cannot be beat. It is a little delicate, however, so don't drop it.
Good Value - the Lavatube...although some users are reporting issues, they seem minor. The biggest beef is that the unit seems to max out with 1.5 ohm dual coil cartos at 3.7V - anything over and it will self-regulate the voltage down without telling you. 'Body Only' Lavatubes can now be had for US$50
Excellent value - Notcigz Infinity and Buzz...solid, American built PV's that can handle dual coils at higher voltages than the Lavatube. No bells and whistles but both are sleek, cool looking devices and very well made and both go up to 5.7V
Provari - love or hate? You don't have to be a fanboi but that much button pressing seems to bug some folk.
Ne plus ultra - the Darwin...although it seems that fatter
tanks won't work due to the swing-arm design.
The latest rage seems to the be the 'variable' voltage system that is actually a switchable Pulse Width Modulation system - see the EVO and the Akston-Hughes SVR...Phil Busardo has a video review up. The 3VO/EVO is actually an SVR repackaged and shouldn't be sold in the USA.