I do not know how well the Danhard AC system SMB installs works without the engine running. I've been told it's not bad, but nobody (as far as I know) has offered up any numbers showing what it does on shore power. I'd like to hear from them.
My starcool will freeze me out with the factory and the DC portion of the Starcool operating while in motion, but my starcool is basically worthless on shore power alone and just can't keep up with the sun baking down on the vehicle. Parking in shade makes a big difference but I'm still lucky to get 15 degrees lower than outside temps. I've yet to see something that doesn't pull huge amounts of energy and agree with Lens.
For what its worth, Danhard (who made Starcool) has a huge selection of add on air conditioners and I might look at seeing if it possible to do a switch.
http://www.danhard.com/revised%20catalo ... atalog.pdf
It's a huge cost though.