RealHotStuff.com is legit. I got a Supercard DSTWO, R4i Gold 3DS, R4i Gold 3DS RTS (Same card as R4i Gold 3DS just released after february 2013) and two EZ Flash 3IN1+ cards. As you could probably guess, I got them for one DSi and two DS Lites, respectively.
Plus they ship ridiculously fast from their USA site. Like TyBlood13 said, it's well worth the few extra bucks.