I’ve had the ETS mid pipe on my 17 WRX for about a week now with everything else being stock. Don’t expect it to be ridiculously loud with the stock j pipe. It adds a bit more grunt and depth of the sound that the FA20 produces with a little more volume, but again with a stock j pipe it’s not ridiculously loud which I guess is a good thing for those trying to keep it mildly spicy. It fits an EOS axle back so I would say it lines up with most axle backs. Be prepared however, to finagle and coerce your axle back because the left side will not be center or hang up where you will want it. Again, with some finagling and coercing you can place it where it needs to be. All in all 4 stars, great sound, mild tone with some small axle back alignment issues.