Looking for KVM switches that will support dual link (2560 X 1600)

I am looking for unbiased exhaustively detailed comparative reviews of high end-(ish) KVM switches that will support dual link (2560 X 1600 resolution) and dual head (two monitors).
I know that KVM switches are not in wide use even among the tech savvy -- so I am having a hard time finding detailed reviews (including front and back images) and recommendations. Can you point me to a site that specializes in KVM reviews? My searches are producing mostly store-front sites.
I need the KVM video connections to be DVI-D (not VGA) [I think that DVI-I would also work as I believe that it is a superset of DVI-D]. Would prefer for the keyboard and monitor connection to be USB rather than PS/2. I would prefer a 3-port switch but can settle for 2 port (and obviously can use a 4-port but do not want to pay a ton of extra money for extra ports that would not be used). Also, the switch needs to support XP and Win7 (so am looking for USB DDM KVM Switches--see link below to paper on DDM switches). Would prefer a model that also switches audio but that is not a deal breaker.

I am currently using an Avocent SwitchViewDVI 2SVDVI10 which I believe is supposed to support dual-link but does not appear to actually support resolutions greater than 1600 X 1200. And I just got a Dell U3011 and want to move up to max resolution. My current switch also definitely does not support a dual monitor setup so it is time to upgrade. (It also does not seem to work correctly switching my Brother printer connected via USB but that is not as critical).

I did find an interesting white paper from Microsoft, but it does not investigate specific models of KVM switches (see http://www.microsoft.com/whdc/device/display/KVM-Win7.m... ).

Can you help me? (Please do not recommend models that are 2-4 years old as nothing that old will have all that I am looking for--although feel free to comment on reliability/reputation of various KVM manufactures based on your experience with older models even if you are not an expert on current models).