It's not for really loading up. You put the large stuff like extra riding clothes, rain gear, that sort of stuff. Bulky stuff you may not otherwise take. It is a great backrest for the wife too. If you don't have helmet locks, you can fit two full face ones in for shorter rides where you don't bring a lot of stuff.
If you need to really load it up, you have too much stuff! It won't break off - it is fiberglass and very strong.