Nice car! Definitely get the Bullitt rims! I had those same rims as you for a year then I got the bullitts! The bullitts are soooo much better, and actually get a lot better traction. Sell yours while they are new and you'll easily get $300+ for them... mine had 36K miles, two curb rashes, and other knicks and I sold 'em for $300 and picked up some Bullitts for $425 with shipping so I got a steal, search and you'll find a similar deal.
A lot of people enjoy the spoilerless mustang. When I first got mine I really wanted a spoiler but now the only spoiler I would ever get is a GT500 spoiler, but it really does look nice without them IMO.
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