Just another perspective --
First...find some speakers you really like and
then buy the proper amp for them.
There are many great speakers at a wide variety of efficiency levels....but
the greatest speaker is the one that sounds best to your ears!
If for some reason, you love the sound of a pair of highly efficient speakers, then by all means get a low wattage, Class A/Continuity/etc. amp...if that floats your boat.
However,
if you love the sound of some less efficient speakers, then buy them and a good sounding non-Class A (A/B, etc.) amp that has the headroom to properly drive them! You'll likely never know the difference between the amp classes.
I don't do stereo speaker setups any more but would probably look at planar (inefficient) speakers again if I chose to get back into this. For these speakers, I'm guessing I'd be much happier with the Vidar than the Aegir. My $.02
FWIW, I keep thinking a Vidar and set of Maggies w/Sub would be an interesting combo for the music that I spend the most time listening to.