From a precision gunsmithing stand point, the Ruger receivers pose some issues when building on them. The old style is better then the new MkII for accurizing of the receiver because you can remove the trigger frame and it will fit in the accurizing fixtures. The new M77 MkII has the permanent trigger frame and will not fit in the fixtures.
These receivers are also very hard and not terribly easy to machine. Certainly not a problem if your using quality carbide or coated carbide cutting tools but they are harder to machine then say a Rem 700 or Savage.
I personally like the Ruger receivers. As far as function, I prefer the newer M77 MkII. For a general big game hunting rifle they work very well and as mentioned, they can make a very accurate rifle as well.
I have several of the Ruger M77MkII varmint rifles that I have rebarreled. My current to are in 22-250 AI and 22-6mm AI and both are easily 1/2 moa rifles.
One limiting factor with the Ruger receivers is length. They can be converted to long actions but its a lot of work. I built a 358 STA for my brother several years ago and it functioned perfectly well and also shot very well but again, its alot of work to convert them.
Without this conversion, your limited to standard length chamberings, not a huge deal as you can get very impressive performance out of this size cases especially using those such as the Dakota rounds and the new Ruger magnum and its wildcats based on it.
Bedded of these receivers is a bit tricky but not a real problem once you have done a few of them and they generally really respond to a propper bedding job just as most flat bottom receivers do.
There are plenty of stocks available for these receivers and there are pretty decent aftermarket triggers as well.
The Ruger M77s do not make my short list for preferred receivers for a precision rifle but they do work and can make a quality rifle for sure. THey make a hell of a general big game rifle and as mentioned already, they are extremely strong for a mauser based receiver. That said, I would never convert one to a Lapua class chambering.