why don't you try KIMONI grip. They are very sticky. Now I am using Prince over grip for my 900P. Not very sticky as KIMONI but it last longer.
yeah, both of kristian and hansip mention overgrip gives good rate from me, i may add wilson pro also
TOWEL GRIP !!!!!!! lin dan, peter gade, taufik top players are using..id unno why towel grip not popular among malaysian player ....
Any brands,and any kinds..really,since it won't really matter,since what matters the most is not the big brand name or the popular model.It's all about ur own preference,since it's not other ppl whose using ur racket.It's u.Make sure u try their tester,since most of the store would have certain models for u to try,or u can try ur friend's grip n ask them what model n brand is it n where to buy.