+1 to hearing lots of cube breakages stories of long term warranty claims, puts me off what seemed a good brand. That must be tempered with the knowledge that every brand suffers from some breakages, no one is immune, its the customer service that should offset that. Even brands like Specialized and Trek, with great reputations for long term warranty and customer service have of late been criticised for poorer service/claim handling than there rep’s of old suggested.
As for selling, pop adverts on here, pinkbike, FB groups (if you can ignore the haterz/phone swappers and general idiots) and maybe a advert but not an auction on ebay