I am almost 100% a natural fiber knitter, however, I think Plymouth Encore is a GREAT YARN! I especially like the Colorspun series, the variegated colors! I use Encore to knit for my little grandchildren so their mom's don't have to handwash and fuss around with drying flat, etc.
I made myself a pullover one time. Very nice to wear. It did pill eventually, but I suppose even the natural fibers can pill, too!
Go for it!