I'm currently in my first two PBEM games and they seem like a lot more hassle/work/chaos than the server games I've been in. But maybe it's just because the server ops were better than average. All I know is I got an email telling me when the turn was ready, I'd login and take my turn, logoff and wait for the next 48-hour notification--just like clockwork. The only problem I had was every once in a blue moon the first connection attempt didn't work but the 2nd always did.
The one thing I think where PBEM has an advantage is in being more forgiving for stales since the host usually delays the game until said staler decides to send his/her turn. Of course, this is only beneficial if nobody minds the delays...
