3" is overkill for the little 305 tpi. however the cost in size between that and a 2.5 is minimal. i'd go for sound. fake dual exhaust. single in dual out pipes from flowmaster probably has the most recognizable v8 tone. i've had several magnaflows and find they have a tin sound. spintech is awesome but expensive.

go whatever you get the deal on, stay away from cherry bombs and flex exhuast lol.

2.5" and a series 40 or 80 single in/dual out setup installed shouldn't run you more then $200 and it will sound good. leave the cat in for the best sound.