I've got one - they're nice in my opinion. Quiet at low rpm, with a deep sound. All stainless construction with 2 resonators. I can't remember the exact diameters, but it's substantially larger than stock. Pipe splits into y behind downpipe then goes back into one just in front of the muffler - hence the 2 resonators. Tip is 5". SP Engineering sold them while they were still being imported. I was told they're no longer available in US. Quality of construction looks good. I haven't had any ground clearance problems even with a lowered car. Jeff