I use ZSH since ages. The only thing I changed recently was dropping oh-my-zsh on favour of custom build with antigen. It works for me. To give some background - I spend a lot of time in the terminal, although I don't try to do everywhere there.

I tried FISH few times but it did not convince me to move away from ZSH.

I think that fish is the best one. However I use ZSH because it has many utilities already created for it

Bash, partly because it's what you get out of the box on most systems; partly because I'm just not sufficiently annoyed by it to learn and maintain a custom shell (yet :)).

I use Git Bash on Windows, simply because it's the closest to an UNIX shell I have found.

I generally don't have the time to screw around with some custom shell; they rarely offer me anything whatever the OS default is, and often using them gets in the way when you need help from someone who doesn't use the fancy newer "replacements"... which is most everybody.

Especially in terms of using Windows which I consider foolhardy to even try to use as a server OS, and which I rarely if ever need the command line for as a desktop OS.

Not to toot my own horn, but you might want to check out my recent story. I really think it might be helpful! :)