I got the 5 hour Revo flash too - about 2 years ago when I first got the car. I didn't ask for it, they just did it for me after a CV Boot repair. I didn't get a CEL or have any issues - and felt a slight improvement in throttle response, which is what they said the flash is good for. It was definitely not a night & day performance difference. I kind of want to go ahead & pay for it after I do my 60K and everything is well tuned. Not crazy about the $1K price tag, but it seems like that's the mod most recommended by techs. I can't see doing forced induction or the RUF type engine swaps.
Off topic - my car always ran fine, and then I desnorkled it 1 week ago. Now it's starting to idle rough & threw a CEL last night. Coincidence? Everyone says the snorkle is purely a noise abatement device, but I'm starting to wonder...
So I REsnorkled it and will see if it runs better. I hate to give up the cool new sound but... at what cost? I hope whatever the problem is, it's minor...