I’ve also heard some good sermons by Baptists.
I’ll have to defer to your “inside info” on the others. :o)
The Southern Baptist Convention does give you a sort of common denominator for theology and administration, but the preaching is all over the map. I've heard some good Baptist sermons -- but I've never heard a boring A.M.E. sermon! Ever!
The most scholarly sermons are usually preached by Presbys (my mother was raised Presby, so I'm a bit of a sermon connoisseur) but I have been highly impressed by the level of theology in the preaching at our parish. Monsignor is solid, informative, and a wee bit dry; the 2nd Parochial Vicar is Irish to the core, very scriptural, a little bit mystical; our 1st Parochial Vicar is the wild card -- he preaches like an A.M.E. (his grandmother was A.M.E.)! He sings, he shouts, he brings Transformers into the pulpit (yes he really did). His nickname is "Father Krunk", and he has a drive time radio show on a local FM station. But his theology is dead center sound.