If you know what you like, "draw wise" that can be of great help. All of SRD's strops are made from quality leather. Latigo's have very heavy draw, while horsehide has very little. (Draw is the amount of resistance you feel while the blade passes over the leather during stropping)
I would recommend SRD's Premium 1. You really can't go wrong with it. It has a soft supple feel, and is "middle of the road" as far as draw goes. It's one my personal favorites...
Having the option to replace parts is great. Also, If a strop is cut, and cannot be fixed, you can always use the remaining leather to make a paddle.