I play a psi warrior and love it. Dimension door is so nice, you can drop the power points to do it instantly too, which is sometimes nice for grappling that caster in the back so you can keep him from casting! There is also an ability that allows you to realize when anyone is threatening you. This works against invisible casters quiet nicely, or just general knowledge. The fact that you have a power that says YOU CANNOT BE SUPRISED in its description is great. I use a psi-crystal as well. I also like the quirks that you can use with most psi warrior powers.
The major thing I like is the fact that I can not be suprised. One of the powers I usually keep up is the threat spell. This is very useful when leading parties, and the fact I can dimension door or expansion myself to size large is fun as well. I pack an AC of 34 at lvl 14. Decent saves as well. Gear might have been better but I rolled him up at lvl 12.
Anyways, I love the psi warrior, gives a little caster flavor to a very solid warrior class. Adding Expanded knowledge feat, sorry book not near but I think thats the name (allows you to take a psion power as your own) this is very feat for those wanting to grab an nice offensive or utility power for themselves.
Also one of the abilities allows you to heal yourself for 1d12 HP. Anyways, I really enjoy the class.