9 1/4 rear?

A lot of talk about rear ends has been going on lately so I thought I would ask. Why not put a 9 1/4 from a dodge truck in? Granted you would have to get it cut down, but parts are easy to find, not to mention the wide array of gear ratios to choose from. Plus you can find them at the local salvage yard reliatively easy too.

So why dont more folks use the 9 1/4 rear? Am i missing something? They seem to be a fairly strong rear end. Pros & cons...?