The fact is, it IS a good ride, definatly one of the best at Thorpe, maybe not as good as Inferno, it's probably on the same level as Stealth, obviously for different reasons, but the truth is that the ride is just a novelty, same as Colossus, Stealth and XWTF, and I believe that is why Nemesis Inferno is indeed the parks best coaster.
And from my example, it's the same with a lot of coaster, you'll find the one's with novelties I.E. Kingda Ka, Pepsi Max Big One, Stealth, Ultimate, Colossus, Rita or Air, won't rate as highly as others such as Bizzaro, Nemesis, Eagle's Fortress, Kawesemi and Piraten and most B&Ms.
The only exception I can really think of is Oblivion which seems to be second favourite at the park and certainly one of the UKs best.