Installing FTB is just a matter of downloading the launcher and running Minecraft using it.
Everything is downloaded and installed for you.
Also, disabling/enabling mods is very much identical to JSGME.
Here's Direwolf's Spotlight showing how it works:
So, if the the server is going to go modded at somepoint, I really dont see any
advantage of compiling our own mods as we did before. FTB includes all the mods
we've used and just so much less hassle.
Btw, the .JAR version of the launcher didn't work for me when I tested it last night,
but the .EXE version works.