Same here, I've had my 2012 Limited Ecoboost for about 2 weeks now and it works great. The overall quality of the car is impressive. Everybody who's been inside can't stop saying how beautiful it is. It has more technology and "toys" than most cars out there. On the MFT side of things, I did have 1 "system is preforming schedule maintenance" reboot that happened out of the blue and lasted about 2 minutes. Other than that, it's been flawless. As for the lag, it is a computer and sometimes if you preform many tasks at the same time, it can take be a fraction of a second to respond after you touch the screen. Be patient and don' t press the buttons a bunch of times.
Overall, very happy with my new Edge!!