I use CueMix with a 2408 and Logic. Works great. It's a little odd going back and forth between the CueMix console and Logic (DP and CueMix are seamlessly integrated, but I'm a Logic user now), but it works as advertised.
no problems here. Logic 8 w/ a motu HD192, 2408mk3 (used to have 24io as well but got rid of it when I slimmed down - but they all worked great w/ logic and cuemix). If you are using cuemix, you don't need Logic input monitoring - you should use the cuemix console instead for monitoring and routing of external equip.