Guys - don't get all hot under the collar trying to project your guessed performance under LMCE of the new driver based on what you see on KDE desktop of a non-LMCE system! I have yet to see any real evidence that the new driver will change anything at all under LMCE.
Certainly, it is unlikely to improve the tearing issue "at least a little bit" as this seems to be a binary thing, either the bug is there or it isn't, it is not a performance thing as the same effect happens no matter how powerful your chipset is. Either way, the issue is triggered when you are using OpenGL + Compositing + Alphablending at the same time.... this is happening under UI2Alpha, but not on the KDE desktop, so you wouldn't even be triggering the issue.
I doubt very much that this issue will be fixed until nVidia get serious about responding to issues and bug reports like this. From what I understand, people have just been stonewalled when reporting this issue. And I can confirm that experience - I reported the bug to nVidia through their official process about 6 weeks ago, to absolute deafening silence. They didn't even bother to acknowledge I had contacted them, and I don't expect they ever will!