Re: OSX and Linux
"A Windows license is ~$200. A day's work for me is about $250"
A RHEL license subscription starts at $799 per year.
Who says I buy RHEL? Gentoo costs $0. Debian costs $0. Ubuntu costs $0.
All three generally JustWork for my needs. Gentoo having the best flexibility, thus what I choose for my own personal gear. At work it has traditionally been Ubuntu, but lately we're moving to Debian for some of our appliances.
I use Windows wherever possible. A days work for me is about $1000. Go figure...
"I'm more likely to spend at least a day of my time just waiting for the usual "Applying Updates, do not turn off" messages"
WSUS is free and manages that for you. This is a good example of why you are only worth $250 / day.
Tell me, can I get a Linux version of WSUS? We don't have a Windows server, and not being traned in managing Windows, it would be lunacy to expect me to manage one.
All the Linux boxes are happy to just do their downloads via a HTTP proxy. The downloads are cryptographically signed using GnuPG and the files are cached so they only get downloaded once. Simple, effective.
How long do you spend assessing all the security vulnerabilities for each platform? I am interrupted several times a month to look at many more Linux ones, but only once a month on Patch Tuesday to look at Windows ones...I spend far less of my time dealing with Windows updates overall.
apt-get dist-upgrade is usually done for me in less than 10 minutes and rarely needs a reboot. The fixes come as they're released, not when the vendor feels it's time to push an update. I apply the updates when I feel I want to, not when the vendor thinks I should.
"searching around for the exact driver, "
That's a far larger problem for Linux. based systems.
I have a laptop on my desk that identified 100% of the hardware from the Ubuntu LiveCD. Windows 7 64-bit OEM (self-installed, not the OEM image which was 32-bit) still fails to recognise some hardware.
I've never had a problem with server or industrial hardware, generally our concern there ends with ensuring storage, network and serial interfaces work. Then again, we're in the SCADA/energy management business, so SATA/SAS and gigabit Ethernet is good enough, and the most "obscure" we get is talking Modbus to an RS-485 bus.
Probably the hardest case I've struck was interfacing to a railway weighbridge and an Allen Bradley PLC. In both cases, it was a case of port the driver: we had the source code for the former, and we were able to get in touch with the company that did the latter. That was moving a system from SCO OpenServer 5 to Ubuntu Linux 12.04.
The biggest issue being the difference between SCO's libc and default serial settings to glibc and Linux serial settings. Easily fixed once we knew what was going on.
"troubleshooting obscure registry problems"
As opposed to trouble shooting problems in multiple randomly distributed text config files?
grep works with text files, not with binaries. Two places does not count as "randomly distributed" to me either. Usually they're in one of two places: $HOME or /etc.
"fending off malware,"
Try running Windows and Linux based internet facing servers. The Linux ones get attacked and compromised far more often. I have never seen malware on a Windows server - only ever on a desktop. But I have seen lots of Linux based server boxes compromised to serve up malware, private FTP sites, Bit Torrent seeds, botnet CC servers, etc, etc...
Have done for years. In 2001 I set up my first internet-facing server. Over the years the hardware has been replaced and the OS updated/replaced. Never had a breech.
This isn't to say my box is bulletproof, it isn't, there's no such thing. Just that I'm not a high-value target.