My 47" Visio has a 5 step adjustment and it has always corrected any problems with lip sync. I admit to not owning a new flat screen every six months, but the picture on my Vizio is outstanding and I'm very satisfied. I would buy Visio again with no hesitation.
As in all things, YMMV.
Home Theater Man Cave: Onkyo 7.1 Klipsch LaScala Mains, Shortened LaScala Klone Center, Klipsch Academy Surrounds and Rears; Panasonic AE8000, Panasonic BDP 460, 117" DIY Screen.
Garage Man Cave: LaScala Industrial Splits; Second hand Denon Amp