I have a SG setup. I've struggled with fit off and on. I think I've got it dialed in now. I have the Krux frame with both the Solo (3300") bag and the Approach (1800") bag. It's really light and well made. Handles a heavy load very good. I've packed out 3 deer in mine this season. That 1800 bag setup is really pretty perfect for day hunting. Its all I've used so far. The Solo should be good for up to 4-5 days of backpacking, hopefully.
My only issue has been with fit with a heavy load, but like I said, I think I have it dialed now. For me I needed the accessory lumbar pad. It made all the difference in the world. All very well made stuff!!