The sound is a loud, deep tone. There is a significant weight saving and the look is ok.
I will try the GPR one tomorrow and see which I like best. The other will go up for sale.
The tail end is in ongoing development, I got a universal tail tidy from an Amazon store, it has an oval led rear/brake light and number plate light in one. The indicators are mounted just under the grab bar. The only drawback is the OG undertray is all in one with the fender, so I had to cut it. I hate doing that to bikes but I can get it to fit back with an under bracket if I want to get it back to standard.