Both are great shirts, huge benches have been done in both!

This is just my experience- the SDP was easier for me to learn. I’ve worn both and struggled with the Rage X. It’s stiffer and the groove is different, which made it harder for me to touch.

The SDP however, I was able to get in and bench without much trouble. The groove of the SDP is pretty forgiving. I was able to work my way down boards and touch reliably without too many mishaps.

Again, both are good. The SDP was easier for me to learn, so if you have to pick, my choice would be the SDP.