which of these two would be the most accurate out of the box..I haven't shot neither before so I could use the feedback

Now this is just my experience, but my M1a NM with either my hand loads or GM Federal would shoot right around 3/4 of an inch @ 100 yards.

The M1a NM can be a rightous weapon but you have to becareful with the bedding (no taking the action in and out of the stock), if you gas system is not welded you wana make sure the screws are locktited in.  But you don't have to worry about adj the gas system, the M1a has better sights and from what I have seen a better trigger.  

Either are good though.