I have a Geissele SSA-E 3.5 lb 2-stage in my LR-308 and I really like it. Very smooth and a nice crisp break. Mine is mostly a bench queen as it weighs 16 lbs.
On my 6.8 AR15 that I hunt with, I have a 4 lb Timney on it that is a good trigger too.
As others said, single stage vs 2-stage is mostly a personal preference. I prefer the Geissele, but for hunting I'd probably go with the 4.5 lb SSA rather than the ligter SSA-E.