I have a Stag lower and it seems well made, easy build up, shoots well. The Stag Head roll mark is a bit overdone but tomato/tomatoe. Nothing spray paint won't cover.
I run a Stag carbine model 3 (right handed) and have never had an issue. Not a real high volume guy but the rifle seems well made. I'd not hesitate to buy another.
Although I'm a lefty shooter too but I just got my 6.8 put together and it's a right handed gun. Added an ambi safety selector and I'm good to go. I had a lefty stag 6L but it was just to heavy for my liking so I sold it. My 6.8 with scope and all of the gadgets weighs less that the stag did out of the box. It shot well and never gave me any troubles though. Black Hole Weaponry just came out with their left hand railed upper so if you want a different lh option it's out there. BHW Left Hand Upper