Aluminum vs. Iron FE block longevity

[Silversmith]

Having never owned a alum. FE sideoiler. I can only speak of my experience with a iron FE sideoiler. A well built 65-67 sideoiler will turn 7,500 rpm for 500 miles on avg. with no problem before requiring inspection and refresh. but it may also let go! As might any engine under that type of load. However, if you keep the same engine built the same way @ say 6,500 rpm. per shift (occasionaly) during general street or occasional track use. Then you can expect solid performance for 50,000 miles before inspection and refresh! Lee Holmon relayed this info to me on the 65-67 sideoiler nascar/block engines. This I believe, because of my prior experience with CSX 3116 with a 66 Holmon Moody built sideoiler! Also because of my present ERA (C5AE-H) Holmon Moody built nascar/block sideoiler. She is not pampered! But if the Pond alum. block is just as strong?, and with the weight savings! That would be just awsome! I must say thou; in the end, I just prefer a well seasoned iron block. But who knows, if I loose this hart. I may think of Alum.