Based on some quick research, but not having seen one, I would suspect there are similar in quality and function to other department store bicycles that you would find at Walmart, Sports Authority, Target, etc...
$310 is probably a bit ambitious but I've seen a newer, 24 speed model being offered up for sale at the reduced price of $450.
Again, if a department store bike will meet your needs this might be OK. KHS, Schwinn, DiamondBack and Raleigh also offer a few low-cost, Asian-made tandems that seem to use slightly better components which may or may not be justification for their somewhat higher cost.
Howdy from Tucson!
Re: Micargi tandem
Rode one briefly, very weighty machine, superficial good looks but beware, LBS had one in for repair. NO grease anywhere! Cost more to repair it than to buy a new one. If your wallet says NO to higher cost, find a known brand used tandem from local dealer or bike swap meet or check TCA classifieds on line, rather than e-bay stuff, is our recommendation.