Perhaps it is because both reviewers and consumer cannot make out which model is the most current. Go to Merlin website and you will be more confused than ever.
Merlins current price list shows VSM-MMM and VSM-MXM speakers, but the Notes section indicates VSM-MXr and VM-MMi speakers. Go Merlins The Evolution of the Merlin VSM Loudspeaker page and it indicates VSM-MM & VSM-MX (Produced from Spring 2004 to Present) as their current model. Now go to Merlin Product new and it indicates that the VSM MMe has been replaced by the VSM MMi and the VSM MXe by the VSM MXr. Why not just label their speakers series 1, 2, 3 etc.