I used vim for 3 years until Sublime Text came out and found I get work done much faster with it. I used the jump feature (forgot what it's called, similar to AceJump on emacs), position stacks, search commands, etc. I installed and learned NERDTree (that's the name) and a buffer management plugin, but they took hours to get used to while editing and many more hours to configure my .vimrc to be somewhat sane. ST came along, and with some plugins, I was able to migrate very smoothly and was introduced to some new editing methods, like multicursors and the wonderful Ctrl-Shift-Up/Down commands for moving lines. No more sequences of characters to perform a common task!

If ST was open source, there would be no need for a competing GUI text editor IMO.