If you’re looking for a KVM switch to use with a DragonFly machine(s), it appears that Belkin (and USB) is the way to go.
I like IOGear KVM switches myself. I have one here that I’m using with FreeBSD 6.0 and WindowsXP. At work I have one that I’m using with WindowsXP and DragonFlyBSD. It works fantastically. They’re both PS/2 KVM’s though. No USB.
I’ve been using one of the many generic PS/2->USB bridge designs (PS/2 in, USB out) on the market with few quirks.* I’ve noticed one flavor of same is now available at Wal-Marts for around $20, so if you just need to flip 2 consoles around it might be a quick-and-cheap option.
*The quirks with mine have been occasional ‘stuck key’ issues using a real Model M, and some apparent incompatibility using an optical Intellimouse with a USB-to-PS/2 adapter, both using a rather old FreeBSD 5.2. Not sure how much of that’s software vs. hardware, so YMMV.
I just wanted to add that the following KVM switch works very well with both DragonFlyBSD and FreeBSD. Best of all, these switches come with cables included. Very nice cables at that too!
DragonFly BSD Digest