Parasound,
Good to hear from you. Thanks for asking about my parents. Both are, thank God, on the mend!
I shipped the Micro Walshes back to Ohm a couple of weeks ago, but I'll answer your question from memory.
The overall sonic character of the Micros and the 100's is remarkably similar. Both have an airy top end, beautiful mids and solid bass. And the soundstaging capabilities of both are tremendous. I doubt that many other speaker designs "energize the room" quite like the Ohms do. They also have a general coherence of sound - a "seamlessness" - that is very pleasing.
So how are they different?
Mostly I think it's a matter of dynamics and scale. According to John at Ohm, the 100s will play louder with less power than the Micros. Additionally, in a side by side comparison, the 100s have an authority or "solidity" that the Micros don't quite muster.
Yet, as I said earlier, their similarities outweigh their differences, so much so that if you're on a budget (and who isn't these days?) I'd audition the Micros first and see how they work in your room. In smallish rooms, they can really get the job done!
