This is great feedback, thank you all. Olychick, you should know that when my bride saw your first post, she said,"Olychick has clinched it for me - we'll have Fantechs, and the builder can figure out how." :-) We may wind up using a single out-the-wall external fan for the downstairs master bathroom, but she was really keen on the dual grille/single inline fan system (one grille over the shower, one in the commode closet). Funny thing is the downstairs powder room is dinky, but has an unobstructed pathway up through the ceiling/attic/roof, so we could use whatever we want for that - same for the upstairs Jack 'n Jill bathroom. Sigh.

WHISPER WARM (and yes, I'm shouting) :) We have them in both bathrooms. Funny story that I've probably already told here. When my husband and a friend was installing a Whisper Warm vent in DH's bathroom a couple years ago, they flipped on the switch, both stood there saying nothing and one of them finally asked, "is it on?" :) It was! They just couldn't hear it. And it works superbly! I can hear it if there is no other noise. It sounds like the very faint sound of water running thru the pipes in the wall. No one else can hear it but I have supersonic hearing :)

I bought a panasonic from http://www.rewci.com/ It would have been a few dollars cheaper than amazon if I hadn't had to pay CA sales tax. They shipped the day it was ordered and it came the next day since their warehouse was only 60 miles away.

I would think the MA-T51 should work. It says no CF, but it can do low voltage stuff. The Leviton LTB3-1LZ looks like it probably will work for you as well: https://www.amazon.com/Leviton-LTB30-1LZ-Incandescent-Resistive-Inductive-5-10-15-30/dp/B002WTC91K/ref=lp_6291360011_1_7?s=lamps-light&ie=UTF8&qid=1531177009&sr=8-7