hardly any difference in sound. for that money i'd get stainless steel mandrel bent pipes from magnaflow or dynomax. If you like the flowmaster sound then get that.
just listen to any 5.0.. from the looks of things you'd think they came stock with em because thats what everyone runs. Flowmasters are somewhat restrictive compared to the other exhaust manufacturers out there. Exhaust is going to be more subjective to your tastes. I like mine somewhat quiet and nonchalant until I want it loud. I went with magnaflows, others like it louder so they end up with borla's, steeda, magnapacks or flowmasters. Theres a ton others out there too. Check out the stangexhaust website for sound samples.
Agreed 100% The true, classic Mustang sound!
Gains with the full catback over weld ins are minimal, but if you plan to add a mid-pipe and/or headers later, you'll want the full catback as opposed to just weld ins. Just my opinion...
There wasn't a big difference in sound bewteen the stock catback and the american thunder cat back until I added a x pipe. Gains from any type of catback or just mufflers are usually pretty minimal.
I think it comes down to if you have a good exhaust shop in your area that will weld them in cheap enough , and one that you know will do a good job on the welding ......IMO , if you dont have someone you can trust to do that , you can get the catback and bolt it in yourself after you CUT the stock system off .....