Shingle, shingle, who's got the shingles?

We went back and forth on shingles. Wendy long ago picked out a pretty architectural shingle (more

expensive with longer warranty). I'd agreed to it but then we had some interesting discussions about spray foam insulation with Tony and Dieter. Seems conventional wisdom says a roof needs to breathe to keep it cool. This is done with either roof vents or a ridge vent at the top of your house and then soffit vents under the eaves which allow fresh air to move through the roofline.

With spray foam, they basically seal up your whole roof. Between the rafters there are no spaces for air to
flow. It's a closed system that doesn't need soffit vents under the eaves. Supposed to be a true encapsulation but some roofing folks were saying this would "bake" the shingles because they never got any relief from the intense heat. They said shingle manufacturers would not stand by their warranty for the shingles if applied.

A few phone calls/emails to Spray Foam Alliance and CertainTeed painted a different picture. Turns out spray foam is still pretty new and not everyone has all the latest info. In the end, shingle manufacturers say temp only raises maybe 1 degree with spray foam underneath, so not much of a difference. Docs get shared saying all manufacturers support spray foam.

But now I realize that with our big gable front and shed roof in the back, there's hardly any roofing that you'll see. So why are we spending more on shingles? Wendy didn't like the change but could see how we could use the extra $750 elsewhere and her second choice was a very attractive shingle.