Also agree- 98% working and much easier than anything else out there.
Was using a VNC callback app but decided teamviewer is much easier in the long run.
Its expensive but it is worth it. And no problems with UAC
Only issues i find
- If you buy a version, your clients need to run that version, not the latest version
- If another software vendor has installed teamviewer, the client needs to exit the tray app before you can run yours
Other than that it works brilliantly.