I bought two aluminum worlds that had known issues with rear seal alignment. After fixing that, one became a street hemi that only made 700. The other was 588 done for nitrous, that hasn't been sprayed yet. The motor made 915 na and has 2 kits on it. I suspect from what the web is like in the block, the second kit, if ever used will cause some issues with the block.

When you compare all the available aluminum blocks, a KB is by far the toughest one out there. The deck, and valley support is un matched, and the web is thick, and well supported.

Since they all cost about the same when you're finished, for me the KB is the way to go. Having to bet money on what will take the most power without failing in some way, the KB would be first, then the indy, then the world.