I have never owned a handheld PS system. How many "good" games are out in comparison to the 3DS? And is the system moddable yet?
There's no guaranteed you can install cfw on your PSP vita, since the save exploits are patched often from sony. There are also many instances of a PSP vita that has cfw (custom firmware) installed, losing its ability to play certain games, sad but true. ... ... ... ... PSP vita is not hacked at the moment to enable vita backs, just the ps1 emulator is hacked, it not worth your time put risky software on your vita, a good portion of users report permanent functionality alterations (not all good).
If you can handle, buying a system where backups are not the best option then keep reading (ignore parenthesis) ...
(I have psp, xbox1, ps2, xbox360 and wii, and most recently a psp tv ... ... ... ... there's a bunch of crap games on the system, however there are some games I consider worth the price of payment, here are the ones I own personally, some I consider buying)
Final Fantasy 4 The Complete Collection (its the most recent update, looks, plays great, lots of new content, and its in 2d) (from psn)
Disgaea 3 (best one outside of Disgaea 1)
Final Fantasy x and x2
Demon Gaze
Super Robot Wars OG (has full character model cursors, versus the "head only portraits" of the "Z" series)
Persona 4 (PlayStation 2 had some fuzzy graphics this version cleans up big time)
(got Final Fantasy 8 and Legend of Dragoon, gona get Chrono Cross later on off psn)
Really don't view much else on the vita as worth purchasing, maybe when i get bored, Operation Abyss, Disgaea 4 (not as good as 3), Earth Defense 2017 (its a remake from ps2 jap, with new content in english), maybe some more used stuff from ebay, don't plan on purchasing much from psn, but I did buy FF4 the collection and some ps1 games. (maybe find a cheap copy of that bloodlines game produced with limited quantities, but its really second rate stuff compared to final fantasy).
also considering buying a psp for psp and ps1 backups versus buying those form the psn store. I have
psp vita tv, really satisfied with the purchase, the games look great and sharp, the game reviewers really like speaking bad about the vita but its all around a great buy.
(never owned a 3DS, but played with Desmume emulator and a bunch of the roms there ... basically it works like this,
GBA WAS THE BEST, NDS was the second best in terms of game quality, and 3DS is a Pokemon Barf Bag, stay away from it! Vita is your best bet!!!)