If you are running several pieces in a rack, it's a must.
It will power all your stuff, and keep the voltage consistant so your tone is always the same.
It's also very convenient to have a single switch to turn everything on.
I have 2 in one rack, and 1 in each of my smaller rigs. I also use it for my recording gear.
They are cheap, good quality, and do their job well.
And the lights are great for a dark stage
