I have just received my Skan Pro1 Chrono and put my new AA S510R TDR through it, or rather the AA Diablo Field pellets in .177 and the results were.
No shots: 10
Mean Velocity: 790.98
Std Dev: 1.49
Mean Muzzle Energy: 11.67
Std Dev: 0.05
I am still waiting for more pellets to arrive and hope the heavier pellets do not put me over the 12ft/lbs.

I am loving the Skan so much easier to use than my old F1 Chrony or the Combro and all the info comes up on my computer to be printed off for refrence.
A bit pricey but worth it in my opinion.