in the first post he uses a SLEH-00448.He is very satisfied with that one.Those playstation eyes, if you have it working, they should be the best.But if you run in to some problems, I think they are difficult to solve.I use a ms vx3000 webcam.For me that one works very good.I tried once a ps3-eye but it didn't went well.I tried to remove the ir-filter and.........now it is useless.
So if you can get them realy cheap, I should go for the SLEH-00448, because at least one guy had it working.He also descripes how he did make it work.For good tracking you can also look at the compablitylist for other type of webcams:
http://www.free-track.net/english/hardware/camera.php?PHPSESSID=74fe0a7e5a9f7934552910065836981a
http://forum.free-track.net/index.php?showtopic=39