Marine Air (AiRRRRR) and Crusair where bought by Dometic (that is the correct spelling for "Dometic"
Marine Aire is a different business. Yes, I believe that your options are:
I know nothing about Marine Aire. I only know of Webasto diesel heaters. Dometic is a fairly well known and trusted brand. Theoretically they've absorbed to two largest players in the marine AC space. I would trust them.
What have you heard about Dometic that concerns you?