We have bought a lot of Indy blocks and have no problems using them for our engine builds. We check the line hone, deck, bore, hone, lifter bush just like any block and have only returned two that were replaced with no problem in 10 years. There are no perfect blocks and ready to assemble out of the box that we have ever seen. They are not marginal as stated by camastomcat in our opinion and we have made good power with them. If you really want to build a engine there is no reason not to use one. The weight of the iron block makes it not worth using in a fast drag car (Top Sportsman, Top Dragster ) We also have seen the older mega blocks fail in short time with good power and have never had a cylinder split in a Indy Block.