I've used both, so I'll chime in.
The Alumitones allow more of the guitar's natural character to come through. I found them to be very full sounding, but plenty clear. I plan to install some into my currently electric guitars. I'm completely tired of any and all buzz and other noise, and I'll be thrilled to be able to turn off the noise gate! They can sound somewhat sterile, but of course, some people say that about EMGs too. They are not as noiseless as EMGs, but they do a great job, even when split (I've not tried their single coils). But, no batteries! That's a big deal for me.