I've stayed out of this thread due to a poster. I'll come out pro garatis. It will have to be at my convenience because I have a business to run and busy right now.
I'll take superheat, subcool, wet bulb, delta t's, attic insulation and ventilation...: Whatever y'all want.
I've seen some marginal sized units struggle to keep up with the Extra latent load this year. That extra 1/5 ton would help, but why is your bill $350?
Wish the company that did my new installation last year did those tests. Way to step up and help.