A dual wheel (DW) base give you not only the ability to pull a larger trailer/5th wheel but also the stability in the wind Vic a single rear wheel (SRW) pickup ...
One of the biggest things people forget is the Dealer you buy your trailer from, be it used or new, there are pages and pages of how owners bought a new or used trailer and the dealer service is horrible ... The best warranty is no good if the dealers service department is truly bad and hard to get anything done or the work is really bad .....
Again before you buy check out the service the dealer provides, I can say it enough no matter what the brand of trailer you buy... I would go a couple of hundred miles if service is good instead of buying local where the service pr warranty work is bad ! ! !