Lots of people think that, thanks to thrust vectoring or VIFF, the Harrier handles like a dream. According to Ward's book, it's only haf true. The Harrier has a poor sustained turn rate and doesn't shine in slow dogfights (*). However, VIFF gives him an excellent instantaneous turn rate as well as hard deceleration. Moreover, the T/W ratio of VTOL planes is in most configurations superior to 1. Hence, the Harrier is a superior energy fighter....
(*) They found out that the Sea Harrier was able to fly at very slow speed at a high AOA, and still be able to point its nose where wanted. They explain it by the thrust wash passing on the tail control surfaces. However, the land Harrier weren't capable of this (if I recall correctly...).