Do you want hens that will lay well too (rhode island, barred rock maybe)? Do you want a breed that is cold-hardy/heat-tolerant (chantecler or brahma, respectively, perhaps)? Do you want hens that will set (dorkings, maybe)? Is personality/docility important to you (what about sussex, brahma, faverolle)? Do you need birds that will be good at foraging, or good at avoiding predators (dark cornish, speckled sussex)? Do you have aesthetic preferences in color patterns, body shape, skin color, etc. (wyandottes, barred rocks, white sussex, etc, etc)?
These are all worth considering when looking at dual-purpose breeds. All DP will make decent meat birds, that's why they call them "dual purpose." I think one of the really neat things is that there are so many breeds with so many characteristics to choose from... I'd narrow it down to a handful that you think would be ideal for your situation, and then start seeing what's available to you... Note that different strains can vary a lot as well, so take the "general breed characteristics" with a grain of salt as you shop around...
Good luck!
