If I recall, the tall deck is the best old GM big block... I believe it's the block that the 572+ crate motors are built off of (only off of new castings). They came in big trucks, and some really hot factory cars I think 427 corvette's had the tall deck, maybe some Camaro's and cop cars, etc.
Anyway, if you want a big inch big block the tall deck is the way to go since you can run big stroker cranks without serious rod/stroke length ratio issues aka high angularity which causes premature engine wear. Because of the tall deck you get the room to run longer rods, which with different piston combination's can theoretically give you a stroker big block with rod angularity/wear characteristics within factory limits. And meaning it should in theory make more power than the same size motor with shorter rods. Because it'll have a longer dwell at TDC, as well as less friction on the cylinder walls. And it will also most likely have a higher safe RPM limit. I think that was the point of the tall deck in the first place, it allowed GM to have a big inch motor that revved more like a small inch motor. But it was expensive to produce so they stopped.
If I could get a deal on a tall deck I'd buy it just because I know they're scarce, they made very few of them compared to most of the other big blocks. That's just me though... If it's the same price as a similar normal 454 or other Chevy big block it's a steal. They're popular among the racers, the blocks are typically more valuable than other GM big blocks.
That is if I'm not mistaken, because I'm just speaking from memory... And I'm not an expert by any means.
