to buy of not 2 buy
 

you guys think there ne good or should i buy another set of cats

high flow vs standard flow cats, there really isn't much of a flow difference. if you plan to keep cats on the car i would suggest jsut getting whatever brand and style will cost the least.
a single 3incher would cost you some exhaust flow over a pair of 2.5's, it would be a fairly significant amount.

im doing a pair of 3" cats

just go with a pair of whatever you can get at the best price.

I went with a normal Catco 3" cat on the passenger side and a Pypes compact 3" cat on the driver's side. The Pypes cat had a small heat shield on it vs these cats you posted that don't. I think the Pypes cat is a little smaller too. I put them on my old 96 SS with Pacesetter longtube headers. Here's a picture of the setup I had. The driver's side cat crossed under the car and I wrapped the fuel lines and brake lines with header wrap and never had any problems.

http://home.comcast.net/~jeffhansbur...-pipe1.jpg.JPG