These are all pretty low power output amps, but the Ditton 44's are very efficient, so can't foresee any issues. My Dad runs an A1 (this the original MF A1 we're talking about here), into a pair of B&W DM602S3's. Sounds very good. Its fully class-a, unlike the B1 and B200, so runs hots, very warm sounding. You can't stack anything on top, mate melted an LP all floppy he left on top! Good amp, but getting on a bit, can suffer from reliablity issues, partly due to age, partly due to hot running.The A1 also has a reasonable MM/MC switchable phono stage.
The B200 is supposed to be very good, all Mosfet amp, same case as A1, but should run much cooler. Not tried one, but always fancied one.
The B1 was a cheaper class a/b amp in the range, think its OK, but no gem, like the A1 or B200.