I haven't personally, but had a friend who just did. He left company 1 due to the erratic schedule and lower pay, but left on good terms. He spent about 5 months at company 2, decided it just wasn't a good fit for him, so went back to company 1. They gave him a schedule he liked and a raise.
Everyone there loves him, so they were all happy to see him come back. No hard feelings or anything that I know of. I think part of what helped is that he is a manager, and also that company 1 was a little short-staffed when he was looking to come back. I'm sure they would have had him back anyway, but that might have helped grease the wheels a little.
If you like the people and left on good terms, I don't think there's a downside. I can see how in some situations it could be humbling, if you made off like you were moving on to bigger and better things (like a lot of people do when they leave places), but even then, it wouldn't take long for everyone to adjust to having you back.