Space is my leader key, save is mapped to <leader>w, exit is mapped to <leader>q, and <esc> is mapped to jk. So nominally exiting from insert mode in an unsaved buffer (jk<space>w<space>q) is the same number of key presses as <esc><shift>;wq<return>, but in practice, in my opinion, jk is superior to <esc>, <space>w is superior to <shift>;w<return>, <space>q is superior to <shift>;q<return>, and <space>w<space>q is superior to <shift>;wq<return>.