i love borla. been my favorite exhaust company for years. they have one of the best sounding exhuasts bar none IMO. thats just the tone i like tho. im not a huge flowmaster fan myself, had it on 2 of my cars and it sounded good on my 99 v6 camaro, but i dont really like it on my gt. too hollow and gargly for me.
it really all depends on the tone you want, and the type of pipe you want ex: stainless or aluminized. yes i agree tho that flowmasters tend to rust, its been the case on both sets of flows iv had. but if your looking for an affordable aftermarket exhaust, youve got flowmaster.