1999 Altima misfire

My check engine light went on and the car started driving really rough, I took it to midas and they said it was a misfire. The car has 87,000 miles. They changed the plugs and wires (the wires twice) but it keeps misfiring. Any ideas? I read on some other messages here that Altimas are picky about what wires you use. What kind of wires should I have put in? I am tired of taking the car to the shop every day.
Thanks for any input

So much for trusting the Midas touch?

Might wanna give a dealer a shout on this one?

what did the check engine light mean. Mine did the same thing, i think, except mine was the distributor it usaully acts up a week before it goes out, mine felt like it was misfiring like a bitch, also u can tell if it is the distributor, u wont be able to pull high rpms, just a thought