I've seen them jam up just fine. Don't let much of anything more viscous than oil to get into the action in decent quantities. Also, at first you can get some problems with stiff springs or lighter loads which will either require manual cycling of the action or clearing a stovepipe. They are by no means a high-tolerance action.
They are fairly reliable rifles as said above but our military switched to something a little more grunt-friendly because the M1A design really couldn't be helped anymore. If you're just going to be sitting under a covered bench at a shooting range there's not many guns that will fail just shooting in optimum conditions.
IMO for the high price of Springfields I would rather get a DSA made FAL, a PTR-91, or save a little more for a QUALITY AR-10 platform (Not a piece of **** DPMS) like this:
http://www.lmtstore.com/complete-wea...on-system.html
There's really no point in buying an M1A-type rifle over any of the modern designed rifles unless you're interested in the nostalgic factor. Same can be said about the 1911 platform (unless you're made of money and really really like the ergonomics).