I really like that PDC, base model with the adjustable buttplate is right around $500, if it works with the KIDD rear tang might be the best solution I've seen so far.
I can say avoid the Mcree Precision chassis for two reasons. First the trigger to grip distance is too far, and second and most important it's 3 piece chassis. The forearm is bolted to the action section and the stock adapter bolts onto the action section, as a result there was a lot of forearm flex. After some machining and steel epoxy it's now rock solid, but had I known it was in multiple sections I'd have never bought it, it's too bad too because it would be really nice if it was 1 piece and the trigger distance was shorter.
A big problem I have with a lot of them is the forearm is way too short, even the "long" versions of some are only 6-7", they need 12+" options to get the bipods out front. PMACA would be my choice if they made an even longer version of the "long nose" which still looks very short at about 7", and they offered an ARCA rail option. The Oryx and KRG look interesting but neither are setup for AR stocks. If KRG comes out with a KIDD compatible version down the road I think it's probably by far the most bang/features for the $.
I really like that Midwest Industries version, haven't seen that one before, but it says it's not compatible with aftermarket triggers, and I'd rather see more handguard interlocking for stiffness, but it might be rock solid too.
One thing so many of these is missing is some way to lock in the rear of the action, you can simulate it with bedding somewhat. I've thought about having my volquartsen, while it shoots amazing as it is, milled for the KIDD rear tang add-on, but the downside is we don't have many good chassis options as it is, and most don't work with the KIDD rear tang. Oryx has an interesting "fix" where the rear of the stock basically clamps the receiver, certainly better than nothing but I'd still like some sort of actual action screw that can be torqued consistently. The Titan spike anchor is another such attempt at a fix.