I use 2m VGA / DVI / DVI-VGA cables in our racks with no issues to date. Not tried longer...

Have also used a TH2GD with a high-bandwith gefen KVM switch in a 2 server backup scenario - as it was a cheaper solution than using 3 DVI switches or a DVI matrix. We used 2m cables between TH2G-D and KVM device. Distribution to projectors was 10m VGA out of TH2G-D (with adaptors)

Never tried longer then 2m cable between Mac and TH2G-D and not tried specifically with TH2G-A

Simon