I have both and I'm pretty much with Scott and Katya - while I've
never had a problem with the eGo/Tornado button, the Riva button feels a bit better. I've timed both and the extra 100mAh gets me about 15-20 minutes more on two tests. The eGo actually does get the 6 to 6.5 hours for me under heavy
vaping. Don't know if Scott ever took apart the Riva to see exactly what battery is in there but if it was the same as the TorneGo, I wouldn't be surprised.
All accessories fit. The cones, charger, mega eGo carts, atty. The thin cartomizers also fit both well, but you have to ream a cone in ordrer to use it - well worth the trouble imo.
I use the Provape's LR, which gets 7+ Watts - iow, great vapor and still maintains flavors. I've seen loaded meterings posted at 3.2 and 3.4 volts and just by experience that sounds about right. It gets better vapor with the same atty as on a mega or regular 510, but doesn't quite match the vapor on a true 3.7v mod - Bartleby.
However, because the Provape's LR atty on the 3.7v mod decreases flavor so much, I've ended up using the regular 510 atty, to where I'm at a lower wattage with my Bart than I am with the eGo/Tornado/Riva with the LR atty. So while if using the LR atty on the Bart I CAN get more vapor (and less flavor), I end up with more vapor/wattage on the eGo/T/Riva than on my 3.7v Bart. That is, until I got the cloudsofvapor 1.8 carto this week for the Bart which
does hold the flavor.
As far as finish goes, the Riva has a more 'matte' finish but I've had no scratches in the TorneGos. I lost one Tornado batt this week - just as someone else posted - an early one in Feb. and it got quite the workout. I also had a batt that had a out of spec center post to where I had to use a staple mod - a pain, but it's still working.
I've only burnout out 1 LR atty on an eGo/Tornado/Riva. And with the exception of ones that have cartoz, it's what I use exclusively from various places - provape.com, heaven gifts joyes, nhaler, CoVapor....