I have been using Sidekick for almost two years now and it acted as a pain killer on my consultant nerves.
I switch context at work quite a bit, plus, being a developer, my Mac is loaded quite heavily at any given time. I just like to keep all of my active projects running at any given time, so that context switching does not hurt that hard.
Chrome having been the biggest violator of my RAM, has always been the biggest cause of pain. After switching to sidekick, the pain was gone, nothing ever freezes, plus all of the web apps that I use are now located in the Sidekick's side panel, which also makes me more productive.