I've had the 163 Non Center ported track with Avid 7T drivers and Roosterbuilt clutching for most of the year on my stock 2014. I only did a few road rides with the stock track and this is my first PRO.
I have really loved how the track just hooks up and GRABS! It's gotten me out of several tight spots when I thought for sure I'd be stuck...
The guys at Roosterbuilt changed the clutching, gearing it down slightly.
I put on 1500 miles so far this season, maybe 1400 with the X3. Towards the end of the year around 1200 miles or so, I noticed some cracks on the front side of a lot of the paddles. I sent a pic of the cracks in to Oregon Trail Sports where I bought it from, they forwarded it to Camoplast and they sent me a new track, no further questions asked. Great service, but I hope the new one lasts longer, don't want to be swapping my track out part way through the year...