Hi,
I have the Micro Grand Refs and feel your MC252 will be fine. I alternate between an MC402, Spectron monoblocks and Thor TPA-30 mono tube amps. The Nola speakers do a great job disappearing. The McIntosh will be a nice smooth listening experience. Please do not hesitate, you could always upgrade the amps later if you desire but I don't think it will be necessary. Please keep us posted.
ps Carl (the designer) likes tubes, but it's not mandatory.