You are right, the Coopers can be very accurate as they apparently really know how to install a barrel. However, their trigger design leaves much to be desired.
I prefer using one of the match Anschutz actions and installing a high quality custom barrel, but I am curious about the custom actions. Does anyone here shoot a Stiller or Hall actioned rifle? I understand that there are a few custom triggers available now that rival the Anschutz 5018.
I have a Stiller 2500X actioned bench rifle and a couple Turbo actioned bench rifles. All have Jewell 2 oz triggers. The Jewell triggers as well as the Bix'n Andy triggers are used at the highest level of benchrest competition. They certainly are as good as the Anschutz triggers. I also have a first year production Cooper 57M and while it's trigger can't be safely brought down to 2 oz., mine is adjusted down to 2 lb. and is crisp with no creep or over-travel and is very controllable. While it can't shoot with my custom benchrest sporter, it shoots extremely well. For a non-target sporter, I think the Cooper trigger is pretty damn good. I also have a Remington 541THB and the Cooper trigger is far superior.
For anyone interested in what the top rimfire shooters are using for equipment, click on the link below and click on the equipment tab in the right upper corner.
http://www.americanrimfire.com/index.php/user/match_results/2143 
