Completos: best places (Santiago de Chile)

I love completos. They might be one of my favorite aspects of the Chilean diet. Sad, perhaps, but true. Eating an authentic completo with tomato, palta, mayo, and whatever else is one reason I'm so excited to be returning to Chile to live. I've sampled completos from a few of the chain-restaurants in Santiago (I think one is called Domino?), and they were pretty good, but I was wondering if anyone could recommend any local places -- pubs, diners, street-side stands, etc. -- that aren't so well known, but truly amazing.

Just curious. ;D