I did the Healtech and GPR can, I did it for the weight savings and sound. I would agree the stock exhaust with the open valve didn't sound too much different. If you're doing the change for the sound only I would say don't, just open the valve. If you're looking to save weight and don't like the look of the stock can then go for it. It does seem a little bit more "snappy" in sport mode with mod. My problem is I can't get my EFI warning light to go off with can and Healtech mod. This I will be starting another thread