There are still problems, trust me, I've run into them. System stability dropped significantly. ANY program that uses a DLL in it's home directory that happens to have the same name as one in the cygwin\bin or cygwin\usr\bin directories will be clobbered. This applies for mingw also. Windows searches %PATH% for DLLs, then it searches the current working directory. Read what I wrote in another thread: http://forums.codeblocks.org/index.php?topic=3550.0
le meow
btw, with MINGW there's only ONE dll, and it's specific to mingw, so I think there's really no problem at all putting mingw in the path. Of course, if you have an executable with the same name of one in mingw tree, you'll have maybe the wrong one when you run it... but then, I think you have really a poor installation on you system.
Speaking about windoze, it's well known that it becomes slower and less stable with time, because of installation of new software, etc... but you'll not solve it taking mingw off the path.
The only way to keep window more or les performant would be e frash install, let's say, each year. I'm thinking to do it like this in my office, as all PCs that I've there are becoming unusable.
I'll make a complete fresh setup with all software I need, and then make a copy of system disk on DVD to spare installation time when i'll run again into problems (which is unavoidable, believe me...)
That's the first reason I'd like to migrate completely on Linux... at least, there you know (or CAN know) there to put your hands to solve problems without having to do a fresh installation.
Regards
Max