Any N1 (huge fartcan style exhaust) is going to be very loud. Also, that slant look is just horrible IMHO. Flowmaster....? you do not have an American V8.
Go with a proven exhaust designed specifically by a company that knows Subaru's:
Those are some good quality exhausts. Cheaping out now will only require to purchase again. Do not rush, do some research and buy quality the first time. IMO Nameless Performance has some great stuff and VERY affordable, if I had an 08+ WRX/STI that is what I would go with.