I like mine. 12 months in Afghanistan with countless miles dismounted. The only drawback I've noticed is that after sweating all over it for a year, the nylon got real stiff and became hard to adjust. I guess if I washed it it would've softened back up, but I had other things to worry about. I was also able to set it up so that I didn't have to adjust the sling when switching from 2 PT to 1 PT. However, I would have to adjust it when going from plate carrier to slick. So it wasn't that important that the adjustment wasn't super easy or accessible. The hardware held up great. Since I got home, I did wash it and it looks almost new.
For the price, the Magpul slings are tough to beat. I also think convertible slings are the way to go. 2 PT when working and needing to use your hands, and 1 PT when you're expecting contact. Worked out well for me.
Now I'm running a BFG VCAS with an IWC triglide. The only reason why I switched is because I had the VCAS laying around and wanted to try something different. So far it's been working out good. However, I haven't actually really used it yet.