If you are "going to spend money" on bars I would certainly not buy "stockers." Several people on here are running PST and other bars with good results. As has been said, you want to "go through" the suspension, replace wear parts, and make certain there's no breakage or cracking.
The bars in mine are unknown aftermarket .......were in a parts car I bought, and are somewhere between .9 and 1". They are "plenty stiff" but not "rough." While I would not want much stiffer, I would not give up the handling, either.
