I would definitely avoid ported applications, when you can use native ones fee-free, especially when it's opensource. For example you can run haproxy on a VM inside a Windows host under Hyper-V, if you're that much into Windows. But in reality I would not either, because this makes you dependant on the Windows IP stack, and I doubt anyone would want this in a production when he has other choices, especially when said stack has bugs like this.
And I strongly advise not to use cygwin-compiled ones. For at least the same reasons, plus nobody, and I mean it, nobody will be interested in a bug if you'll find one in a cygwin-compiled application. It's hard to make a bug-report developer-friendly, and this task gets -9000 karma when you are reporting a bug found in a cygwin-compiled software.