I had 3.5R's which are slightly different. That being said, 200 watts tube or solid state is the least I would use with them. My room is large, I listen in the high 80's
spl to a wide variety of music.
If your room is small (not likely with larger Maggies) and
you listen at low levels, then m-a-y-b-e...
Unless you can get in and out of the 40 watt amps without taking a financial hit, I'd say nope. If you can afford to try them then go ahead, nothing to lose.
You will need a bit of luck though, larger Maggies are a pretty stable mostly resistive load, but require current to open up.