The Joye 510 model (i.e., the Titan and the Cignot kit) has been very popular for the past two years. It
was one of the two models that I used to recommend to new vapers. And the 510
atomizer (or cartomizer such as Drew recommended) continues to dominate the
vaping scene. For the past year now, however, there has been a much better
battery for that atomizer/cartomizer: the "fat batt" (e.g., eGO or Riva). It provides many more puffs per charge than the standard 510 battery (650+ mAh vs. 180 mAh). As my nickname indicates, it is a somewhat wider battery, but certainly not huge.
Liberty-Flights sells a
750 mAh two-battery Riva kit ("Riva 510 - Special Edition") for the same price (after applying the 20% discount in the upper left hand corner of the screen) as the Cignot 180 mAh Joye 510 kit ... and it is higher voltage than the Joye 510 (or eGO), providing a more intense
vape.
That is
one of the two e-cig models I recommend (e.g., in
this article). The other (simpler and more convenient to use) is the Kr8. Until recently, the quality of the
vaping experience didn't quite match the 510. A couple months ago, Bloog introduced the
MaxX Fusion Mini. I am (and many others are)
very impressed by it. I reviewed it last month here on ECF:
http://www.e-cigarette-forum.com/fo...13-maxx-fusion-finally-vapable-supermini.html The same size as a 100s analog cigarette, it provides an
extremely satisfying vaping experience.
It is, however, more
expensive: $90 for a full kit (including two batteries, five cartomizers, and a PCC that will be needed to frequently recharge the 220 mAh batteries). If your sister-in-law is willing to make that upfront investment (with ongoing costs no more than the Joye 510 or Riva), this would be an excellent choice IMO.