uunix & Linux
An interesting choice with many plus points but also with some down-side.
Solid, used for more web-site servers than any other operating system type and easily usable as a day to day desktop.
Millions of applications, majority being free. Thousands of choices for which variant you want. Completely Open-Source, with more on-line help than any company in the world.
So what's wrong?
- A lot of different distributions. Meaning sometimes there is no Standard!
- Skill set required draws a larger premium. Cost of support normally higher.
- A lot of main applications are not available (although there are normally Alternatives).
- Local, low cost support companies thin on the ground.
The above said, Linux is a definitive choice for a server, but remember that, if you're using it as a mainstream user server, you may pay more in the long run.
uunix, will not charge more to support Linux systems.