I'm a lefty. If I were buying a bolt action I wouldn't buy a LH model. If I were buying a DI AR style I would buy it LH. They expel a good amount gas out from the bcg and with a lefty using a RH rifle that is RIGHT in your face. Needless to say if you're looking at the model 8 (piston driven) I might not rush to get it LH. It's a few dollars more for an LH model and you bet you can spend that $$ more wisely (read as ammo, optics, other "needed" accessories).
I thought and thought about this when I was shopping my AR. I ended up with a PWS, which is a long stroke piston driven AR, there's a little bit of gases that you deal with but the bulk is expelled out the gas block. I added a Magpul BAD and i'm good to go. The shells NEVER hit me (well at least not in the face) as they're extracted and it's a bad ass rifle. Would a lefty version have been better? Maybe, but PWS doesn't make one only a small handful of manufacturers make a dedicated LH AR. And I don't k ow if I would have paid the up charge for it (usually its 10-15% more for a LH model).
Bottom line, for a DI rifle IMO its worth it to get the LH for a piston drive, not so much. Worst case is with a LH model you can tell your Friends they cant mess with it cuz they're righties.
SIG 1911 .45 ACP
SIG P229R 9mm
Beretta BU9 Nano 9mm
Beretta 84FS .380 ACP
Ruger MKIII 22/45 Target .22LR
PWS (Primary Weapons Systems) MK114 5.56