I think the best approach is wait until you get the set and evaluate the TV's performance with your own components and service providers. You probably will not notice any sync problems and then you will not have to add the Felston (or similar) into your setup. We all tweak our HT's to improve performance. Sync, like PQ, sound quality and many other other areas is a possible area to tune.
But, let's face it, many of us are hobbyist's and the Felston sounds like a fun piece of equipment. If you need to delay audio and your receiver can't do it, then it would be nice to have.