I currently use OM, and can't say I would recommend it.
if it breaks, I'm just going to use it as a really expensive 4 way splitter with all ports constantly on. when I was waiting for my replacement motor, I removed the drum and just let it go full flow on all 4 ports and it seems fine and no sand blowing around. it was out of warranty so I haf to pay for it. I think OM is a two person operation (husband and wife maybe?), and for an item with no price listed, the price I got quoted was different depending on whom I talked to. not a good way to do business imho.