I found an article on Petri that explains how to install OpenSSH to Windows via cygwin. I know that OpenSSH is basically the standard SSH server for *nix distros and was wondering if that means it's better suited for Windows as well? There's also freesshd which is native for Windows and I imagine runs faster as a result.
I've never used freesshd so I can't make specific comments on its quality or reliability. The forums do state "Please note that there is no official support from the author for freeSSHd or freeFTPd" so you should not expect any more support than you get from OpenSSH via Cygwin. The product does not seem to have had any updates since Jan 2009, so I would err on the side of OpenSSH via Cygwin.
Also with Cygwin's OpenSSH port you are using as close to the same code on windows as you might already be using under Linux/BSD/etc so compatibility is relatively assured and you will already be familiar with the command line syntax.
Remember that OpenSSH is command line only though, even on the client. If you want a GUI for SFTP/SCP then I suggest something like WinSCP.
freesshd may be slightly less work to install and initially configure, but I've used OpenSSH via Cygwin on many Windows hosts (from XP to 2008) without issue and you have the advantage that you can install bash, find, grep, and friends at the same time which is a big win if you are familiar with those tools from other environments.