I didn't buy anything from Miguel (yet). However, I wanted to express how great it is to deal with him.
Recently I was interested in a pair of his headphones. Miguel responded quickly and informatively to each and every question, and even asked other knowledgeable Head-Fiers to help where his experiences left off. He even tried to dissuade me from buying them because he felt I could go with a different option which might be better for my situation (Which kind of sold me on his character if nothing else).
In the end I didn't buy from Miguel, but it was only because I got a smashing good deal elsewhere on another headphone I've been interested in (and as such my wallet is depleted).
I would highly recommend Miguel to others if you're interested in dealing with someone who's responsive, informative, patient, and goes above and beyond to make sure you're getting what you need (Although I must say this means he probably shouldn't pursue a career as a door-to-door salesman

). I never had to wait more than 12 hours for a response from Miguel, and most of the time I received a response almost immediately.
I am looking forward to dealing with Miguel again, and I have no reservations about doing so.