I did go with the highest bidder and it did not matter. They did a shoddy job and threatened to take me to court when I pointed out mistakes that they made based on their work standards stated on the quote. I have not paid them yet, just filed a complaint with the BBB. No money down asked, no contract signed. The boss stated I have to high of expectations just because I live in a 121 year old house!
Deciding which paint to use has gotten much easier now that acrylic latexes have pushed oil-based paints almost to extinction. The acrylics offer superior performance (they don't harden with age, the way oils do, so they move and breathe without blistering), they don't mildew as readily, and they emit fewer VOCs, so they comply with new air-quality regulations. They also work over both oil- and water-based primers.
His team is very meticulous, very careful, very clean, and very courteous! They're also very accommodating. For instance, I mentioned a couple spots under some angled siding where I thought a little extra filling was needed, and they obliged without question. Same thing with a request for a stain-proof primer under a balcony. Doing these kinds of little things without question or extra charges is really nice!