I've got a two month old high mount ti M4 with a ti mid pipe that is near immaculate. I was planning on upgrading to a full M4 exhaust, so if the price is right I would go for it.
This pipe sounds awsome and looks awsome. The guys I know that have carbon are regretting the choice after seing this bad boy. Hammy did me justice by recomending this pipe.
The only blemish is two small marks from hitting the mid pipe with my shoes (it's going to happen). I was going to try and take them out, just haven't gotten to it.