Sinclair should be on the Gen 3 model by now - there is one version with a fine-adjust head, and one without. Basically the 'ski' type bipods like the Sinclair, Centershot, Remple, etc. tend to work better with a light(er) hold and not much shoulder pressure. Trying to run 'free recoil' will get you in trouble with the rules in NRA F-Class, but its possible to have such a light hold that the difference is somewhat moot.

More 'traditional' bipods like the Harris, GG&G, Atlas, etc. seem to work better for a lot of people if they can put more shoulder pressure against them, sometimes even digging in the feet and going with a 'hard' hold.

I have a couple of the Centershot bipods, a Sinclair Gen 2 and a Gen 3, a couple Harris BRMS bipods with Pod-Locs, and a GG&G. The Sinclair pods work great for some folks - but I have a hard time shooting consistently with them, not sure why. The GG&G is about the lightest one out there (10 oz) but doesn't have notched legs and is hard to get locked down hard. The Center Shot pods are fairly light (1 lb 4 oz) and work slick, but can be somewhat delicate due to the carbon fiber pieces and a lot of joints/connections/moving parts.

When its all said and done... I keep a Harris BRMS with Pod-Loc (and Pod-Paws) in the side pouch of my gun case and a spare bipod stud installed on the fore-end rail of my 12 F/TR. The other models have some nicer features, but I can shoot just fine off the Harris when need be.