I just purchased 3 'refurbished' Sol units directly from AI (Very reasonable shipping, too); I contacted AI and was told the units had minor cosmetic defects from manufacturing on the heatsink and/or unit casing but they were NEW units that didn't meet 100% on QA.
They do not have these up often (They also had Vegas for -$100) and only in limited numbers.
Saved $100 bucks on each unit. They look brand new (all original packaging, power adapters, etc) there is some slight flash on the plastic casing (I got black - you absolutely cannot tell when they are mounted.) and one of the units has a shaving of plastic in the puck housing that I'll have to remove before running these full time.