USB Keyboards: Recommendations for & Life Expectancy of

I'm relatively new to USB peripherals.

In the past year, I've had two IBM USB-1 keyboards die on me. I have a
Logitech marble mouse hooked to a port on the keyboard, and run it
through a KVM 4-port to USB-2 ports on the computer.

Is the 6 month life span an attribute of:

USB Keyboards?
IBM USB Keyboards?
USB Keyboards attached as I have it set up (KVM+Mouse+USB-2)?

Since I need to get a new one (and a backup as well it would seem),
any recommendations for keyboards? I'm looking for:

USB
resident port to add a USB trackball
perhaps programmable buttons, but not required.
good key action for a skilled touch typist
lifespan longer than a few months
not visually garish (no racing stripes, neon strobes, etc)

Many thanks