1st choice: Jim's locks are excellant and require very little work to make a very "slick" lock. Most of his internals are well polished were needed. His frizzens are properly hardened, frizzen, sear and main springs have a good tension, not to heavy and not to light, just right.
2nd choice: Davis locks are also very good locks. I have used Davis locks on my last two builds. I find that Davis locks are of a very rugged design, they need a little more polishing of the internals to make a "slick" lock than a Chambers lock does. The thing I like about the Davis locks are that they have some differant designs that work well in the Colonial and golden age period. The Davis locks I have used have had properly hardened frizzens, good springs and all functioned well.
My last choice would be an L&R, I don't like to talk badly about these locks becasue I think they can be good locks but require much more work than the other two on the internals to make a good "slick" lock. There are a couple of things I do not like about the design of their Manton styled lock. First if you are not carefull the pivot arm of the tumbler to mainspring can be put in backwards. If you do this you can break the "ears" on the tumbler that holds the link or pivot arm. Second is the fly rides on a pin on the underside of the tumbler. If you are not and experianced builder it is very easy to get the fly in backwards. I have used a number of these locks because I like their style but I hate the fly arrangement. The last L&R lock I used was a Queen Ann and the mainspring arm that goes under the bolster had to be ground quite a bit so that it would clear the barrel. This is not a big deal, just another step to make the lock "fit" that I don't have to do with the other makers locks.
All are good locks and much better than I could build for their price.
