So if I understand you correctly, Meridians lack of support or development for their officially released QNAP Sooloos core and storage app motivates you to buy an MC200

My concern with a QNAP/MS200 (or QNAP/218) combo is the near future possibility of the QNAP component part being made effectively obsolete by Meridian's failure to update their software sufficiently as part of QNAP firmware updates.
My concern is not with using QNAP purely as a back-up device.
Therefore, an MC200, whose software/firmware and hardware characteristics are wholly under the control of Meridian, appears to be the more robust option.