Just thought I'd attach the document Mark at Motec sent me on setting up CAM control on a Motec
ECU.
Definitely worth setting it up if you have an AVCS capable engine. Don't assume that yours is setup properly as there is a good chance it isn't as most tuners don't / won't take the extra time to setup AVCS unless you specifically request it and if you do it's not going to be cheap.
Note that if you do start to use it then it WILL require a complete re-tune of your fuel, timing and boost control maps so expect some dyno and/or road-tuning time (thanks Rossco and Jester) to get the best results.
Enjoy