VDE in the 5.0 is not similar to AFM in the GM pushrod engines. Roller follower with solenoid driven hydraulic spring pin vs collapsible lifters on the GM. On the 5.0 system (also used on the I-3 engine) issues are unheard of. The system is disabled with Sport Mode and Tow/Haul mode and also is smart enough to disable itself if problems occur (in which case the spring pin plunges back into the activated position).That's why I went Ecoboost. I had the AFM system in a GMC and didn't like it. I'd rather run on 6 all the time than 8 only part of the time.