Finally got to use my new SF-5x's. Prior to buying these I tried out:
Scubapro Veloce Club: my default, good overall. 1.2'/kick cycle.
Scubapro Jet fins: incredible thrust, foot pocket too wide for my foot.
Scubapro Twin Jets: couldn't find a kick style that didn't cause me to cramp. Caused soot out on a wreck dive.
Mares Volo Power: too little resistance, lost thrust.
several other fins from various other divers I've come across....
Love these Tusa's.
Fit: For my size 7 5mil wetsuit boots, the foot pocket is a little deep, but allows my foot to stay really secure. Fin strap doesn't have a loop like my Veloce's so it's a bit harder to take the fins off. I end up unbuckling.
Power: I haven't been back to the quarry yet to measure kick cycles. Finished my 800m stamina test in 12 min 35 seconds with these. Didn't even feel tired. Don't have a comparison using my default fins, yet.
Maneuverability: Like other poly fins, I can turn on a dime and instantly kick. Feels good.
Kick styles: These fins felt great when I used frog kicks and flutter kicks.
I'll update this thread with more scientific/quantitative measurements as I get them.
Edit: BTW, pictures do not do these fins justice. The silver/black look much better in person and I've gotten many compliments already.