I'm a fan of convertible slings from 1 to 2 points. The Magpul first generation slings were inadequate, they fell apart. Since then, Magpul has addressed the problem (and sent me a new one, free of charge), and their new slings are of pretty stout construction.
Mostly, I like 2 points. It's more comfortable and useful for hunting or actually carrying the rifle. A one-point sling is more for the heat of combat (or airsoft as I use it). But it's nice to be able to go from one to another easily. I'm not a fan of quick detach slings, because I believe the are less versatile since many rifles have conventional attachment points. Magpul carries both types.
Whatever brand you go with, make it a good one. I bought a tapco sling for around $30 and it was terrible. I could have sent it back in, but basically I had to resew it to get it to work, and the included clip wouldn't work at all. As with many things in the gun world, it may be tempting to buy a cheaper product in the short term just to have it now. Resist this temptation. You will likely end up spending more money and have a bin of products you do not use any longer and end up buying the more expensive product later down the road.
However, if you are not going to use your gun much in the field (literally, in the field--hunting, airsofting, a carbine course, or war/duty), then you may never wear your sling out. As for me, a couple of seasons of airsofting was enough to shred a more poorly designed Magpul sling.