904 or 727 ?

I wouldn't run either without a bolt in sprag! I have blown up 2 904s & both times the sprags pooped the bed! Cracked the case in 1 pretty good. Both were behind a 318 making maybe 350HP in a street driven 67 Fastback. I switched to a 727 because I was given a car that had 1 in it & I was sick of pulling the 904s out. I have to admit I felt like it lost some power after the swap. The 904s were bone stock except for a B&M shift kit in 1 & a Transgo in the other.
I'm probably going to put a 727 behind the stroker small block I'm building in my Dart, but thats mainly because I have a built 727 w/ a 3500 converter & a matching driveshaft sitting in my workshop just waiting for something to do. If I didn't, I'd probably build a 904, but I'd beef it up a lot more than I would if I had to do a 727 again.
People will always tend to give advice in favor of what they are using. The fact of the matter is you can make improvements in both to make it work. The 727s internals can be lightened & the 904 can be beefed up. Which way do you want to spend your money? Just don't do it 1/2 assed when it comes to transmissions. Too much can go wrong quick.