This isn't an Arcade monitor correct? I did a quick search on it but just want to confirm with you.
If not I don't think there is really a point to get the ArcadeVGA. These cards are more for Arcade monitors, so they can run the correct resolution and refresh rate.
With non Arcade Monitors, you are probably going to be doing some hardware stretching in MAME anyways, so you can just use your standard ATI card. You'll never get the correct resolution and refresh or make it look like it does on an Arcade monitor anyways.