I happened to have two IBM WinXP laptops on my desktop tonight as I was installing the NX client on one of these machine before my brother goes to China at the end of the week.
Anyway, I had a remote NX desktop running on his machine to my colo Xen machine about 256kbps (50ms) DSL away and on mine I had the local NX desktop which I’ve been using as a test install for the past two weeks. Compression was set at modem speeds for the remote and LAN speeds for the local desktops. I decided I need a test to show off NX off to him and figured a quick look at my gallery would be good. And it was. It surprised even myself.
The remote desktop loaded this page faster than the local desktop. There was a definitely noticeable difference in page display speed in Firefox. The quality of the remote desktop on the two screens was hardily different. The thumbnails on the remote were slightly blurry, but not by much.
The remote machine is sitting next (Xen-wise) to the gallery web server and obviously my local desktop load the thumbnails over the DSL link. So this is a certain testament to NX’s performance given that same page and images were rendered and presented faster from the remote location.