SourceTree has become very slow of late and literally freezes for several seconds with a beachball. In addition, there's almost always a lag while typing in the commit window. I think this all has to do with the background refreshes that are going on. Weird part is on my second MBP with the exact same specs, where I have only 2 small repositories, I still see this lag. It's getting to the point where I'm thinking of going back to SmartGit as it's hurting productivity.