I wanted to check out a Sage XP I got recently, and it led me to an additional experiment. I thought it might be interesting to side by side several generations of rods covering quite a few years from the same maker. So, I took out the 9/9 XP, a 9/9 RPLXi (5 pc) and a 9/9 RP which I've had for quite a while now. I switched the same reel and line (Airflow 40+ Intermediate) and fly back and forth; conditions were fairly benign.
The XP impressed me with very low swing weight; uniform crispness but not a broom handle. By far the nicest of the 3 to cast.
The RPLXi (which I hadn't cast before) also nice and light, but the tip took some getting used to. The tip seemed slightly softer than the rest of the rod causing a slight delayed loading type of feel. However, the rod definitely got the job done and that softer tip might make it a great rod for the back country creeks where you are casting 12 ft one minute and 60 the next.
The RP (when did I buy that?) had a slightly higher swing weight and was slightly slower so wanted a bit longer stroke. But damn, still a sweet rod.
Some time I'll want to cast all three with a more conventional WF taper and see if any impressions change.
Disclaimer: I don;t work for any tackle co. or sell any rods. I only buy & use them (mostly Sages and Scotts).