Same here. I use spaces in JavaScript source files, but tabs in Go. Would be nice if this was handled automatically as its easy to forget. This is one of two blockers preventing me from switching to Textastic (second to symlinked folders not being followed in the sidebar; bug already filed). If not for those two things, I could see myself switching from BBEdit.

Almost always because two different projects are using shared code from another folder on the system. E.g.

sharedlib/

project1/

sharedlib/ (symlink to ../sharedlib)

project2/

sharedlib/ (symlink to ../sharedlib)

We use mercurial at my company and this is the easiest way to have shared code in separate repositories while still having access to those dependencies from all projects (we have a convention of cloning all of our repositories in a single top-level folder so all relative symlinks work for all of our developers).