There's a brand new preview of the full version of UT posted today comparing the D3D vs Glide performance...it's looking good for us G400 users who will be using D3D. 
Here's the relevant quote from the preview:
"...we've already previewed and playtested Unreal Tournament....D3D is now working and it's looking absolutely fantastic. The only noticeable difference to the Glide version being texture pre-caching delays on loading a level."
The full review is here:
http://www.gamespot.co.uk/pc.gamespo...uk/review.html

Here's the relevant quote from the preview:
"...we've already previewed and playtested Unreal Tournament....D3D is now working and it's looking absolutely fantastic. The only noticeable difference to the Glide version being texture pre-caching delays on loading a level."
The full review is here:
http://www.gamespot.co.uk/pc.gamespo...uk/review.html
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