If the BPE heads flow anywhere close to 290cfm unported, they should work well.
Working with a semi-clean sheet of paper, as they did....... I don't think it would be that hard to improve on the rpm head.
BPE heads are CNC ported as delivered. Brett was involved in the port design. Bischoff( BES racing engines)does the CNC porting and valve job. Both those guys know how to make proven power. Extremely nice work. Looked at the heads last summer at Norwalk.
I think they will capably support 650 horsepower with right combination.
