Went with spray foam, not batt, and I'd do it again
Standing seam vs. shingle was the hard call, but the insulation one was tougher. Picked closed-cell spray foam for the whole shell of my 2,400 sq ft place outside Austin. Cost $11,500 more than batts, and the crew took 4 days longer to finish. But after a summer hitting 106 in July, my AC runs half as much as my neighbor's identical floor plan. Has anyone else regretted cheaping out on the thermal envelope?