Headroom is always one of the first places I look when considering a new amp, and I have come very very close to buying a variety of their products, yet somehow never have. They just never seem to hit the exact feature/aesthetic/price balance for me, even though they are one of the few companies I'd trust to build a really competent product.
As noted, at the low end, the Airhead/Bithead line is aesthetically way behind the times. I've been tempted a number of times by the Micro amp/dac for office use, but they are stuck in this weird no-mans land. For office use, they don't need to be that small (and hence use 1/8" input jacks, for instance) especially since the freaking power supplies are bigger than the components.
I was very close to buying a portable micro amp/dac as this is a nice all-in-one unit without an enormous power supply, with good connectivity options, that I could use at the office, and still bring with me for desk/hotel use on my frequent business trips. I like the size, I like that it has some weight so it shouldn't slide around the desk from the weight of connected cables, but I honestly didn't need the batteries, and for some reason, Headroom designs their battery powered amps to be battery only - so for the most frequent use - on my desk, I'd be constantly charging/discharging, rather than being able to leave it plugged in. Also, the portable micro (which is rarely available used) costs as much or more than their Desktop amp on the used market, which uses considerably better parts.
Anyhow, it all boils down for me that HR really just needs to tweak their offerings a little bit, and I think they'd have some killer products. I'd love to see that happen.