Both the vita and N3DS are easily hackable (assuming you're on a vulnerable firmware), and both will handle everything up to the 16 bit era just fine. If you go with the N3DS, you will also get native DS and 3DS gameplay. If you go with the vita, you get flawless PSX and PSP emulation through adrenaline, plus native vita gameplay. If you go with the vita, the only thing you need to purchase is a vita-to-microSD adapter. If you go with a N3DS, you will only need to purchase a cheap DS flashcart if you wish to play DS games. Obviously both require microSD cards, if you don't have one lying around. I have both, and both are quite good. I do somewhat prefer the vita for it's nicer, higher contrast, higher resolution display. However, there are more compelling games (IMHO) for the DS and 3DS than for sony's handhelds. For purely emulation of older systems, it's basically down to your personal preference of form factor.