I just want to bring out some points.
If there was something wrong, did they offer to fix it? Clearly so.
They fixed your bumper for free which you didn't even show any pics. You can't even say for sure if the other shop did this or not.
Now the problem with your engine. Your car is not new. There are things that could go wrong and I know that they would look into and try to make sure its resolved. Impressive has been in business not because of one time scams. They have been in business because they have continued to offer reliable and good valued service for many years. Lets be clear about this. Years, not 1. Not 6 months. But many many years. They have a lot of experience with these vehicles. You have a vehicle that needs special parts. They don't keep cars because they want to. That place is always full of vehicles and they NEED to move cars out of there.
Every business is going to have unhappy customers which we should understand. But if anything happens the Impressive shop is always trying to make it up. Everything you said they have tried to fix. So yeah, its ok for you to post your experience but make sure all the facts are there.
A good business is a business that tries to make the customer happy even when he's unhappy. Impressive has offered to fix anything for you. If anybody can't read then go up there and read it again.
Impressive Auto Center