Have to agree with stutho, are we actually talking about custom or non custom first of all, then we can take it one step further than custom, I have a cutomised custom Expr all made by keven at bridgewater to my specifacation, which I beleive to be the best bike on the planet, without sounding to proud.
All joking aside though I beleive that if it suits you and you like it there is no one single winner, but the general feel does seem to be for the sherpa / nomad is there any more expr riders out there to support me please.