First, while certainly possible, it is not really cut out to scale to the enterprise, and doing so will require intimate knowledge of the system.That said, MacOS Server has some drawbacks, of course.

While this is not the subject of the question, even being more expensive than Windows clients for the initial purchase, Macs have a much lower TCO in many environments, if users would stop thinking in brands and reputations and instead start to learn what the real differences and pros/cons are, beyond the logo and the more or less fancy GUIs.Even if you plan to run a Win clients only or mixed Win/Mac environment with a Linux server and Samba in a 10 to 20 user environment without a pro admin, I would recommend using MacoS Server in many cases, as it shields all those implicit complexities behind an really easy to use GUI.At least with simple requirements, the promise of not needing a pro admin is much more realistic for a Mac only shop than for any other platform. Scaling out is another thing, but this requires detailed knowledge on any platform. In my experience, general administration is much more easy than on any Linux system and also than on Windows, at least for smallish groups.Telling your users you don't support these might be possible, but it also might break some applications. Naturally, it also has full support for all the small Mac client specifics like resource forks, finder attributes and stuff like that which all have the potential to become a real PITA if you use a Win or Linux server instead.It allows for an extremely easy creation of features comparable to Win group policies for Mac clients, much more easy then to do the same for Win clients on a Windows server. MacOS Server offers major advantages if you use Mac clients in you network.I was about to write an endless essay about the pro's and con's, but let's make it short instead. With no real Mac Server hardware and the Server software being just a cheap add-on to the client OS X with dramatically limited usability and functionality, newer OS X server versions (10.7+) can't be reasonably used beyond small workgroups, preferentially in Mac-only shops. Edit, as this post still gathers the occasional vote: All of the points below are now irrelevant.

Apple server os