IMO the only reason the explorer UL would have less durability is 1) It is _really old_ and has not been taken care of well. 2) It is mistreated and scraped on the ground or rocks. I am 5'10" 240# or so and the Ultralight is a sweet hang. Keep it out of the direct sun and take good care of it and you won't have anything to worry about. The biggest complaint I've heard about the Scout is the size is not really sufficient for a full sized male adult. It seems to be more designed for shorter folks. I know some women who really like them and they were designed for scouting so kids are the intended user.
I have mobility issues and so the bottom entry is the only entry system I can use. In that regard the HH is my hammock of choice. It has never "let me down", barring user error.