Just a quick remark about your thread title. Technically a Diamondtron NF tube is an aperture grill type. The other manufacturer who produces aperture grill monitors is of course Sony whose tubes are sold under the Trinitron brand name. The simple way to pick out an aperture grill monitor is to look for the shadows cast on the screen by the pair of horizontal stabilizer wires.
The two monitors you have listed then are very similar in terms of features, refresh rate etc. As such I really can't make a recommendation about which one is better and you will like more.
I will say that I have a Diamondtron NF tube (probably the same one as what is in the Diamond Pro 920) in my iiyama i90a. I have been very pleased with the image. I did own a Sony monitor before my iiyama. To my eye it seemed the Sony had somewhat more vivid, richer colors. I have since looked at other monitors with Sony tubes and would have to say that the majority produce a somewhat more desirable image than what is displayed on my iiyama. But THIS IS ONLY MY OPINION. Everyone has different tastes when it comes to monitors.
