I've played two full campaigns with the Turks myself, and i found them easy to play. From early on i allied with the Egyptians, so i didn't have to worry about my back, and i attacked the Byzantines who have large lands and are quite vulnerable in the beginning. I conquered all their lands and stopped my advance after sacking Constantinopel. From there i concentrated on beefing up, and preparing for the inevitable Mongol invasion, chopping my former allies the Egyptians to bits in the meantime. Piece of cake.
Btw... did anyone try that link i posted earlier in this thread ? I'm curious if anyone played it yet, and what their opinion of it is.