My 165 is a lib snowmullet with reg btx. Spinning off natural features only. Haven't rode a nice pipe for years they are getting harder to find, but when I did I like a stiff board with good edge hold. I'm not sure that the trs has a progressive side cut, lib has it marked as a 8.45 on the 159 and 8.5 on the 162. My snowmullet has a progressive sidecut and its labled 8/9. The sidecut is so close between the two sizes that I don't think you will notice a difference, though at 8.5m its longer than the average board. If you want an even longer side cut look at the lynn or lando pheniox they are around 8.75m, they are directional twins so they have a bit of setback, but I perfer that when carving. I actualy perfer reg btx over c2, I like the looseness and better pow performance, I mostly ride pow and I can make any board rip groomers. I've been eyeing the gnu dirty pillow 162. long sidecut reg btx and a pow shaped tip and tail.