On the slants and mild aplications the alum. OD trans is fine, and would be fun to drive around with. But the only downfall is that it doesn't hold up to hp very well. I've heard of people moding them so they do better... but for higher hp the cast iron case is the way to go.
One of these days I want to get the whole front clip ( steering, suspention, Etc. no sheet metal ) from one of those.... It would give me a huge differance in ride on my '56.
