This topic has probably been discussed ad nausem. Still I'd like you
guys opinion on what to choose. Brand, model, power, delivery,
weight, size, the whole bit.

One big enough to drive a nail gun, no more than two, is sufficient
for me. I like my emglo 5hp gas wheeled twin barrel. It is way over
kill and works only outdoors. I am looking to get a second, smaller,
portable electric one.