Douglas makes decent barrels, way better than OEM, but in my humble opinion they are still far from the best out there. You get what you pay for.
I think the PTG trued actions are probably a pretty good deal but I've never purchased one so I really don't know for sure. I would expect that they would at minimum make sure that everything works properly vs factory. The last time I was at a gun shop, 6 out of 6 brand new 700s had very poor bolt timing and could never properly extract a tight cartridge without beating on them. Remington's quality control has never been awesome but ever since their brush with bankruptcy, it's been downright horrible. I would fully expect PTG to filter this all out for you. If not, I bet they would accept a return.
One thing is for sure. Buying a trued action by any of the folks you mentioned is almost guaranteed to result in a better hunting rifle than buying one off the shelf.
If you are not hurting for cash, consider saving up for (or just splurging) on a custom action at double the money instead. At double (or a bit more) the money you'll get 5x the value today and many multiples of that in the future because custom actions don't depreciate over time like factory actions do.