I use vim
Why? Because I use vim everyday for my work (editing and viewing input and output files of scientific software). Because vim just works (no need to compile, upgrade to the newest version, setup third party repositories, etc.). Because I started creating ebooks before Sigil was even thought of. Because I'm a nitpicker and want full control on the code (I will spend some time indenting and aligning stuff in the OPF file!).
I still want to try using Sigil for real, but I'm lazy
