I get your point......I have been in a similar situation myself.The company i work for has offices across united states,europe and asia employing about 500 people all across.Sometime ago we needed a web collaboration tool to manage our resources across all our offices and to better manage our workforce.
We did some initial testing with a few vendors but almost all of them had similar problems like deployment issues,compatibility issues,downloading of some kind of software to make it work,problems with the low bandwidth etc etc.We tried everyone out but disappointing results.
When we were almost about to give up ,one of my friend suggested Turbomeeting by
http://www.rhubcom.com and to this day we have never faced any kind of issues with it.The best feature what i really liked was that it didn't need any special software to be downloaded or jacking up your current IT setup.You can easily integrate Turbomeeting it to fit alongside your firewall.We really got what we wanted,i would advise you to have a look at their website product page
http://www.rhubcom.com/web_conferencing/product.htmlCheck out the features,i am sure you will get the solution what you want right from Whiteboard to Remote access....everything.
Dan