off topic, I can confirm that logitechshop thing is for real, though the owner of the store is a colourful bloke, usually called Fast Eddie on the whirlpool forums.
As for sleeping IEM's I can't vouch for the RE-0's as they feel like a small rock in your ear when you turn on your side. Actually, recently I was shocked to discover that the Apple earbuds, with their lack of edges and flat profile, feel extremely comfortable to wear while sleeping, almost as if they were designed around it. What a weird world. I'm guessing based on that that in fact many ear bud rather than IEM designs will feel better when sleeping because different angles of pressure on an earbud won't make them dig into your ear canal.