It looks good for speed climbing. The fastest I ever climbed Mitchell was 2.5ft. per second, for me, the ropewalker has been slower, as my maximum step height is way shorter with it. Here's my experience listed in order by climb rate speed:
Footblock: self rescue, because it hurts my foot after a while Longest climb: 30ft. 2 times in a row
Texas: Best used for multi-drop caves when carrying almost no weight or no pack Longest climb: Neversink, and many nuisance drops
Frog: Best for multi-drop caves when carrying ropes or packs. Longest climb: 408ft. of footage, many TAG caves
FrogWorm: Best used coming out of a long, deep, drop after a hard expedition. Longest climb: tested 1,000+ft. in both Neversink and Cagles Chasm
Ropewalker: Best for efficiency over long haul on deep drops and footage.
Mitchell: Best for speed when not carrying a heavy pack on multiple pitches without much caving between. Longest climb: Golondrinas
Murphy: Best for speed on deep drops. Longest climb: Neversink
M-system: yet to be tested...