727 or 904?

Wow... people are passionate about this topic!
From what I can see, both perspectives have their merits. I'm only likely to race a couple times but the reason I'm building a performance car is cuz I want it quick! Quicker than my bros bowtie cars especially! lol I will drive it hard but I won't be running it on the edge all the time. If it costs a few bucks more to speed it up a little (but still be reliable)... I'm doing the 904.
Cost isn't an issue here. I'm not rich but I get parts pretty cheap and the labor (and some training) will only cost me lots of cold beer but not much else. Friends helping friends make the world go around!
904; I think the list of 'parts' is fairly clear but I'm not sure about the valve body differences that have been mentioned. I don't mind the manual shift but do I need it for my application?
Since he's the one who has to build it. I'm going to take this thread with me to my trans guy for his opinion too.
Awesome discussion, thank you again everyone!

... and holy **** those exploding drums!!