I used RL17 and H4350 when working up loads for my 243 and the 80gr TTSX. I ended up sticking with RL17 because of accuracy, not velocity. Although the RL17 was slightly faster(40-50fps), it was much more accurate in my particular rifle.
My concern with RL17 is temp sensitivity. After it gets good and cold here, I'll shoot a few and comparare notes.
