I've recently been offered a similar sounding table that has the same label and wasn't sure what to make of it!
Have you managed to find out anything about them?! They are very similar to Merrow tables and my initial hope was that MDA stood for Merrow Design Associates, but I have my doubts!
MDA = Miller Design Associates. Different companies/designers. The Howard Miller tables are nice, but aren't in the same league as Merrow in my opinion.