I have read that it is faster, though I have not tested it myself. Personally, my initial reason to use it was just to try something new and explore the unix world. My reason for staying is that it is a very simple init system that is pleasant to work with. It made me understand what an init system is and use it a lot more.
Systemd is good if you just want something invisible and you do not want to mess too much with an init system unless you have to. Everything integrates with it
OpenRC is nicer if you want to write your own init scripts. It is very well documented also.
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