I've played and beaten:

Tales of Symphonia
Tales of Symphonia: Dawn of the New World
Tales of Legendia
Tales of Graces f
Tales of Xillia

I'm currently working on Tales of Xillia 2 and having an absolute blast. It's a long term goal of mine to go back and play all the Tales games I haven't gotten around to yet. I love this series.

Tales of Hearts R will likely be my first Vita purchase