I don't like slings. They get in the way and get caught on stuff as you move. So, I avoid them if possible.
Sometimes they do provide a necessary service though.
I have used a couple of single point slings. They tend to put a lot of weight on your neck. If you're going to be carrying the gun all day, consider a 2 point instead. They spread some of the weight out over your back. For longer periods I find this better.
I have a Magpul MS1. It will cost a little more, but the one hand adjustment feature is first rate. Being able to adjust it with one hand is really handy when going from moving to shooting.
I also have a Magpul MS3. The one hand adjustment is better on the MS1.