The main benefit of aluminum rods in what we do is to help the bottom end --keeps caps from walking even on Megablocks--they act like a dead blow hammer--it used to be one of the ways we kept stock blocks alive when -1 Indys first started making some real HP--they are all about the main caps not weight--and in a stroker like you plan steel rods are sooo much easier to get in there and not hit the cam etc so if you have an Indy block or KB block then it becomes less critical
Again I say Charlie Buck has built more 1000--3000 Hp engines than all of us on here combined --ask someone that really has the experience and knows