originally played Descent with pure keyboard as the mice at my school where clunky in-keyboard trackballs. later we moved on to quake and i was forced to start using a mouse which had been upgraded to actual mice by this time. when we migrated back to Descent after our school's headmaster mysteriously learned about all the pentagrams of protection we were hunting, it being a catholic school and all, i found that i could not go back to keyboarding it.
i do have an old ms sidewinder pro joystick that i've tried to use from time to time but i keep going back to the mouse because the accuracy is just too precise to pass up.
currently using a logitech MX1000 with the Cruise Up/Down keys re-bound for pitch Down/Up and the Tilt Left/Right re-bound for Yaw Left/Right to assist so i'm less likely to run out of mousepad while tracking a target. banking is done with Q and E since i'm stuck firmly in the WASD config from most FPS gaming. but arg if i don't have to suppress the urge to mod all the ships to allow for at least small amounts of lateral, vertical and reverse thrusting...
if the mouse support is enhanced as mentioned
here which sounds suspiciously like Freelancer then
