Roebling used to have a huge bump in the faster turn on the track which would launch people directly to the hospital, without needing to use a helicopter cuz it was so damn fast! lol CMP has also been repaved in the last couple of years so both are very nice and smooth now. Not sure what dirt you're referring to in T1....never had any issues there. It's more technical and challenging than Roebling, which is why I like it more. I'm not very good at CMP at all, but I do like the layout. I'm much more competitive at RRR, but that's cuz it's an easy track and everyone is decent there.