I too have found this, with one exception: fork/exec is appallingly slow. This means ad-hoc scripts in Cygwin should be written as much as possible as pipelines and not loops; bash string functions should be used over sed, grep etc. whenever you can help it.

But with that caveat in mind, Cygwin turns Windows into an acceptable Unix for command-line purposes.

I don't think it's quite as good as a development environment when you're targeting Linux though. That's where WSL (in either form) makes a lot more sense.