>One thing I recommend to my clients who are fussy about their keyboards/mice and have settled on unusual ones: buy 1, 2 or more spare units. At some point HP will stop making those without warning. If you have one fail, or you want to use one on another computer you're out of luck unless you want to take your chances on eBay etc.
The worst shopping mistake was the 5$ keyboard from IBM, at Big Lots, of all places. I bought only one. Should have bought all six.