Is there any significant performance/load time impact if single web page will load, say, 10 identical flash objects? 20? 30?.. any evidential data on sustainability of such kind of setup?
This would be the same flash app, each instance serving its own stream.
Best Solution
There's definitely going to be some overhead in size as there is a certain amount of code that is contained in every swf regardless of it's developer created content.
I'm almost certain there would be speed issues as well, which would see frame rates drop right down the more swfs you add to the page.
To be honest the concept smells a little fishy and i would think there must be a better solution to your problem.
EDIT
Also there is a restriction on having two steams coming over http per domain. Sure you could get around this but it will definitely be an issue.