vi supports tabs! Well, not really... but if you want to have a handful of vi sessions open in a session, there's always suspend, and then fg "vi filename" to switch to a suspended session
When I first started using UNIX, I learned to use ex for editing configuration files. I wasn't really involved in any complex scripting - mostly a glorified babysitter. As time went by and I needed to coax more than basic functionality out of UNIX, I switched to vi and never really looked back. I don't even think about the editor, really... it's more reflex than conscious choice. That's probably the best compliment that I can give any utility...
Now, I have vim installed on the Windows box here at work, as I've grown tired of all of the letters that started to crop up in notepad. yy, cw, hjkl, etc.
nb: I use SciTE on Windows to troubleshoot the odd grammatical issue with a complex script, or when I need to provide printed documentation of the script.