The first thing you should think about is if you have both a PS3 and a Vita. If you have both then I suggest getting the Cross Buy. If you buy the PS3 version, then you will get the Vita version for free to download. A great deal if you ask me.
The next thing is that the game has cross save. If you play on the console the data can transfer to the Vita and visa-versa. Pretty unique feature and useful for travel.
Pros
- Cross Buy and Cross Play
- Contains 20 unique characters from the start of the Playstation up till now
- Customization for characters from the taunts, the victory songs, to the clothing
- Online mode contains custom matches and ranked matches.
- Invite friends to fight and have a 2nd player with you with another controller
- Absence of some popular characters, like Crash Bandicoot, and Nathan Hale. Though there is going to be DLC featuring more characters
- Trophies can't cross over. Though the save data can be transferred, you have to earn the trophies on both systems separately.