Rocio Del Mar Liveaboard
Have done Socorro twice with Rocio Del Mar. The boat and the crew are both fantastic! Food is great, and they did a great job accommodating my vegan diet (and making me a birthday cake). Cabins are a decent size and configured to have reasonable space for getting ready for dives.
Amazing big critter diving, with abundant mantas, white tips, silkies, and dolphins (the one dive I skipped on the last trip was the one at Roca Partida where the whale shark showed up).
Would do it again in a heartbeat.