The bb5's in my mind are just like the others by way of power. They will set up easier because they have the CPS(caliper positioning system) which is basically that they moved the mounts on the caliper a little bit so they can fit some V-brake pad washer in there.
The bb7's are so sweet mainly because they have an outboard pad adjust. There are a few other things like a spring tension adj, but I've never noticed that making much of a different. The pad adjustment is nice though because you can move the pads closer together and still keep the whole lever arm throw so your modulation is a lot better.
Compared to hydros I can't really say. I've had three sets of bb7's and never felt like it was necessary to move to hydros. The 7's have been adaquate and I feel like if I go to hydros I may not want to go back, and I also don't want to have to buy a bleed kit or mess with that stuff, like EVER. So whatever.
I just make sure to get some nice compressionless housing and run full housing with stainless cables.