There is a far less elegant, but more affordable option I found (after following your link). Gefen makes DVI switchers that do not handle USB; use one of those in conjunction with a cheap KVM that is $40-50 and you have a cluttered but inexpensive solution.
The total, $520, is $330 less than an integrated solution from Gefen...
For a two port KVM, the all-in-one Gefen does seem to be the better choice; $139 (2 port Belkin) + $250 (2 port DVI-only Gefen) = $380 vs $449 for an integrated Gefen...