I have heard that gar can be tastey. Not that I have tried them personally. I'll stick to my panfish when I want to eat fish.
However, I will say that gar can be fun to catch. During the dog-days of summer (like now), when its too hot to do any good with other fish, we'll go out and rig up minnows about a foot deep under a small float. I like to use the natural cork balls ~3/4 inch diameter. Cast the minnow toward an area where you see them close to the surface, or where they are 'gulping' air. When one takes it, put the reel in free-spool, and let him take line for 30 seconds or so, so that the hook will actually be in his mouth, and not just out on his beak amongst all those teeth. Then set the hook, and have a fun battle.
Note: Removing the hook can be dangerous to your fingers, so it may be better just to cut your line.