Since PCS still hasn't released their kit for the Allison, Scott said most folks are tuning with EFI Live. Parts are definitely bigger in the Allison, though it has more parts and it is a very complex unit, especially electronically.
So far, most folks are unable to use 6 forward speeds in high power conversions. The rumor is that the Allisons don't hold up, only safe with 5 speeds. Would be nice to have the 2 reverse gears. Its mainly about matching up clutches.
Anyway, a 4R100 won't require the expense of a transmission controller in our Fords. Instead of an overdrive unit, i just went to taller tires. I'd love to be informed of a test between the best built 4R100 and the best built Allison 1000. Some hard facts on paper and results from tests in trucks would convince me. Almost every transmission guy i've talked to believes the 4R100 is the strongest light duty truck option.