Thanks Grumpyvette! Finally found the information stated in an article due to your link.
So that no one elese need look through it all for one piece of info:
For Boosted applications, H-beam rods seem to be the way to go, it appears they can be a bit lighter than I-beam and still handle the larger low-rpm compressive loads, or the same weight and handle even more.
For high rpm engines, either rod works, but once again, the h-beam will be a bit lighter.
Thanks again Grumpyvette!
Brad