Enjoying this game immensely in single player. Can't play co-op with a friend though, never able to connect. I can play public co-op though.
I also found an interesting bug in single player, where if you zipline near the bottom of a broken powerline near the ground, it will zipline you underground, falling into water. (Found only in one place, not really tried anywhere else) You can swim around, look up at cars driving past, trees etc. There are water areas and if you swim out of that block you freefall forever, then if you deploy wingsuit you immediately die. Interesting to see what goes on under the map.