I can't vouch for the DA 7400 stuff since I've never used it myself. I does look nice though. I've been trying to put together a group, but it's been way hard and looks to be as expensive, if not more than SR. Cranks are way hard to find and the brakes go for alot for used stuff. For the price, I'd rather get the SR, although the long term usability maybe better with DA 7400, since you can still find chainrings and 7sp FW.
Plus, IIRC, somewhere in the evolution of DA, they messed with the parts so it was incompatible with the rest of the Shimano line-up. But I think this only applies to indexed shifting. Can someone verify this?
I've been trying to find a single front 7400-series brake, and it's been impossible. For some strange reason, I've got this lone rear brake...
However, my first race bike had Ultegra 600 7sp (which I still have) and it works great in either friction mode or index. Too bad it has that stupid dark grey finish. I'd absolutely LOVE to have another complete set of this stuff.
In sunny LA with no time to ride.