I'd "picked" some Peerless 710 ASSA Desmo cuffs (Assa cylinder lock) with Double Lock set.
The Double Lock is set by a Pin which is pressed with a small wire into the casing to prevent the Teeth on the cuffs to be lifted even with the right key.
I put the cuffs on behind the back, smashed them on the carpet floor (which was unsetting the double lock) and than shimmed it with a small Metal flap.
even offhanded I was not able to Pick that ASSA Cylinder, to get the shackle off it's not neccessary
All in all it took me roughly 3 Minutes to get out of these "high security" HAndcuffs.
Standard Handcuss lit you geht them in the "toyshops" are basicly poor quality lever locks simply lifting the blocking feather... (which can be done with any stiff item you can get through the keyhole.
Also the shimming is quite commom specially if there is no Double lock set and can be easly done from bearly all positions of the Hand.