OMG, played Gley Lancer back in the 90's. A friend of mine had it. It's a great shooter.
For those listing shooters, there are tons that are fun. The others I loved not listed are:
Alien Soldier
Gaiares
Curse
Bio Hazard Battle
Bioship Paladin
Musha
Atomic Robo Kid
Truxton
Grind Stormer...