I'm looking to set up an OpenBSD server myself. Things are going quite well, but I'm not looking forward to the upgrade process (as an example, here's 5.4 -> 5.5 http://www.openbsd.org/faq/upgrade55.html). How easy has it been for you to upgrade?
Would you recommend the patch by patch process or the full check out code and compile?
1. Install a release.
2. Subscribe to the security list.
3. Patch any issues that turn up and may affect you using the instructions in the patch. Rarely this requires a reboot. Don't patch anything you don't need to.
4. Upgrade release a couple of weeks after it is released (everyone else has found the bugs then ;-)
5. To manage ports, subscribe to the ports mailing list, create packages yourself from ports on another machine and install them and upgrade them yourself if there is an upgrade or security hole posted.
Before you do anything though, test it on another host properly. YMMV with all updates on all platforms.