Well, is not that easy, it involves first running the demo on a supported device (I used a Nexus One for this), and after the first run it creates some data files which need to be copied to the other unsupported phone after running at least once the demo. You will need to have the phones rooted if you want this to work.
Performance of the demo on the Nexus One seems as good as the Nexus S.

I've never been able to get the demos to work. It just crashes on the galaxy S. Did you have to tweak anything for it to work?

I have made the ImageTargets demo work in my Nexus S, so I guess it would work in a Galaxy S also.

This device is not currently supported. Support for the Galaxy S should be added sometime early next year.

Please see the device compatibility sticky for more info:

http://ar.qualcomm.at/node/2000017

- Kim