Checking coils

I found rust on 2 of the coils connectors while putting on new wires. Just wondering if anyone has noticed this or am I looking at new coils?
I cleaned the connection with some steel wool and used dielectric grease when putting it all back together but the car seems to be lacking a little power and has a small miss at idle. Has new plugs and wires. Coils???

I'd run it to Auto parts and have it checked. Normally coils either work or they don't. If one didn't work, you'd have 2 cy. that weren't firing. You'd notice that kind of quickly.
http://img.photobucket.com/albums/v425/kustomkid54/1998PontiacGrandPrixGTP002.jpg