Depends on your budget. I used an NAD M3 with my Adagios and it sounded very good although was not strong on air and detail. The detail was there, but not forward. Very good bass, soundstage, not fatiguing at all. Very powerful, meaty, and substantial sounding with the Adagios. Plus, it had tone controls so you could turn up the treble if you wanted to but I never did. I only sold it because the display is small and I couldn't see the volume number from my chair. Dumb maybe, but whatever! Now I'm using a BAT VK300xSE with the Supertube option. Compared to the NAD it doesn't sound as powerful but does have more air, detail, (this sounds silly, but) "tube magic".
The NAD can be had used for around $1400.00. My next choice for SS would've been Sim I7 because it also has a large display like the BAT and twice the price like the BAT. Others to look at might be Plinius 9200, Cambridge 840A V2, Anthem, or the MF you mentioned. Then there's Class D like Wyred4Sound, etc but Class D didn't suit my preference. All comes down to synergy and preference but I think the Adagios like power. (disclaimer: I like power)