amplifier for Magnepan LRS

That will be a fine match.

I have 2 classDaudio SMA amps (125 watt@8 ohms/250 w@4 ohms) driving Magnepan LRS and MG .05 speakers. The preamps are Anthem AVM 30s'.
Both speakers sound excellent at low levels and at rock levels.  Even at low levels the speakers can be attention grabbers when reading.  Sound stage details increase as the volume is increased. Going thru all my music files with these speakers.

I'll be using an Anthem MCA 225 amp (225w@8 ohms,400w@4 ohms,600 w@2 ohms) with the MG .05 soon.  It was driving Martin Logan CLS 1 (w/1995 panels), but the treble was rolled off 12 db (new panels are +$3,400). 

At 120 watts into 8 and 210 watts into 4 ohms it should be a great match. Happy listening.