Valdore Dimensions
You can see a image of the chart if you go to concept artwork included on the Nemesis communicator download from the official site-Its not useful for detail but gives you the idea.
If you play SFC3- There is an Nemesis add-on that lets you play the Scimitar-included in the 10 meg download is a folder of wallpapers it is the concept artwork for all the vehicles in Nemesis-There are 3 different size images of the scale chart.
There are links to the image which is popping up all over the place.
Nice artwork for the Valdore
Go to the Taldren website click on forums look under StarFleet Command general discussion.
In Star Trek Communicator issue 141
Page 52 Is the FX companies size comparison Chart for the Ships in Nemesis.
The Valdore is
604.5 Meters long
908.3 Meters wide
Hope that helps
The Official Site mistakenly gives the D'Deridex Class Warbird stats listed under "Romulan Weaponry" to a picture of the Valdore. As you can see by its size this vessel is roughly half the length of the D'Deridex Warbird.
"To be honest, my opinion of starfleet officers is so low. You would have to work very hard indeed, to disappoint me."
Senator Vreenak to Sisko.