Piecing together information from this thread, a glory run is 25 seconds at best and it takes 7 runs to cover the cost of one death. If world hopping adds 4 seconds each time (total of 8 seconds added to the trip) and we assume that the inefficiency of running south to level 30 wildy vs using the obelisk accounts for an extra 5 seconds (being generous, I'd imagine it's more than this), then in an hour of regular running, you would do 144 runs, but an hour of cautious running would be 94 runs.

Even if you died 7 times in an hour, you break even. Any number of deaths less than that and it's more efficient to stay in a members world. Keep in mind a lot of these numbers weren't gathered by me or they were very coarsely estimated. This is just a very rough calculation.