At 400+hp, What kills A904s?

Cuz you can't bolt them to a big block or a hemi...if you could they'd be all over the track. It's a small block tranny that started life as a slant six tranny. Nobody wants to post prices on these "indestructible" 904s...Is it $4500 for a "good" one? $6000 for the best? You can't even rev a stock one over six grand without shifting into third by itself. You 904 fanatics always act like a stock 904 is bulletproof and when anybody questions you on upgrade prices, you run for cover. How much is it for a 727 billet drum and bolt in sprag? Oops, can't take the extra tenth in the quarter?