You really cant go wrong with T-5's. A friend I used to ride with had pro circuits and they were really great pipes, T-5's just a tad bit better in my opinion. Also T-5's respond very well to porting, unknown as far as pro circuits go. A great and easy package you can square away yourself is T-5's, up a tooth on the front sprocket to a 15, lighten your flywheel ,advance your timing, cool head with 20cc domes and your good to go, until you start to get spanked by ported bikes, thats when the big bucks start flying outta your wallet.