I have ported many sets of heads over the years and always liked the 452's, that being said if economics are the main factor then I would suggest the Eddy's.

The ported 906's will have an advantage over the unported 452's but will not be as good as the EDDY's. The 906's will not have hardened seats for today's gas unless someone had them installed whereas the 452's and the Eddy's will have hardened seats from the factory.

just my

Joey