I swapped my Thermal 3" for a Thermal 2.5" that a local guy had. We both got what we wanted. The 2.5 is nice and quiet mostly, and still roars at WOT.
However, he had the CVFab downpipes on his, and his midpipe was expanded to fit. So now it's kind of loosely on my downpipes. It's only being held in due to the next pipe being connected.
I also didn't like the 2.5 tips and put on some tips from Amazon that look like the 3" version.
I ordered some stainless steel shims to go around my whoosh downpipes so it can fill up the expanded space. I am also going to try a T-bolt clamp there instead of the accuseal type. Hopefully the leak will go away.