I just got my new system (with a 1901) in today, and I haven't had much time to play with it yet. I played maybe 10 minutes of Halo and Descent 3 (because I didn't have anything else handy, and Decent 3 blurs pretty badly in places on my Samsung). From what I can tell, the 1901 DOES have a faster response time than the Samsung 191. There's still a SLIGHT blurring, but it appears to be far less than the 191 (which is itself considered a good panel). From what I can tell, the response time isn't going to be an issue for me with this monitor.
Also, it seems to handle resolution switching better. 1024x768 looks almost indistinguishable to me in Halo as compared to the native 1280x1024 (aside from just the difference in resolution).
It's possible that difference is due to the video card somehow. This is hooked up to an x300se (basically a Radeon 9600), while the Samsung is hooked to a Geforce 4. From the settings, it looks like maybe the x300 is set by default to handle resolution scaling on its own, rather than letting the monitor do it, and maybe it's better at that than the Geforce 4.
So from a VERY short time with it, I'd say it's equal to the Samsung 191T+ for most stuff, but it's a better gaming monitor.
Unfortunately, I do seem to be having one problem with it. It has a built-in 4 port USB hub, but when I plug that into my new system, the system usually freezes a few seconds after booting. If I enter the BIOS, it'll just hang after a second or two, and if I let it load Windows, it'll usually hang saying it can't find ntldr. VERY scary. I thought my whole new system was screwy, but it really seems to just be the USB hub in the monitor.
I'm going to have to figure out what to do about that (if anything) tomorrow. I've never heard of a USB hub actually preventing a computer from booting. The extra weird thing is, if I plug it in AFTER the OS is loaded, it works fine, but reboot and it'll hang again until I unplug it and reboot. Took me a while to figure this out. I pulled out just about everything else from the system before I thought of unplugging the USB cable?