Hi Jo!
Have an eGo and thoroughly happy with it. This model has earned all of the accolades it's received. But I almost lost one of my eGo's, so I felt it prudent to get backups.
Don't get me wrong because I love my eGo's...but I went with Rivas.
Several reasons: great
reviews, larger battery capacity (750 mah), better button (also lighted), better looking (imo), all hardware cross-compatible with my eGo, and significantly cheaper (2 kit for 49.95 at VaporJunction).
Actually I just bought
batteries ($16) and cones in platinum and black because I already have the other parts. Was in the mail less than an hour after placing the order on Friday and just awaiting shipment.
You absolutely will not go wrong with eGo's. But if you want a unit w/ a little longer battery life that looks a little nicer (again imo) and save some $$, you might want to check it out.
btw Jo, so that you don't have to keep saying "K8(something)" or "510(thing)" please read the following threads (gonna be worth your time, promise):
http://www.e-cigarette-forum.com/fo...rated-guide-e-cigs-part-1-6-a.html#post552767
http://www.e-cigarette-forum.com/fo...c-cigarette-first-time-vaper.html#post1438697
Happy hunting!