I own 3 choate set, an old version and 2 which have front and rear swivel + a locking "nut" on the rear pod!.
All bought thru Brownells and came with adaptor.
I own also two bipod, Harris 6-9 and 9-13, model with leg notchs.
HBBRM 6-9" (leg locked at 6") really low on the bench !.

When shooting from a bench, i use front leg notch and a rear wood block 3-4-5" and the infinite adjust of the rear pod to set the rifle :


You may see the front and rear swivel of the new version and with a little imagination the blocking nut (sorry, if someone have the right expression, he is welcome.)

HBLM 9-13" , like Tim, is fairly high wood block is mandatory even with the shortest adjustement.

Leg notch are 1" spaced and look like :

PS:
The bipod is tighned on the adaptor and it is loose on the sides so it had a little roll. I use 2 piece of wood to tighten the mount :
