Shaan's forte is soft romantic numbers..since the original king of soft romantic numbers Sonu Nigam has more or less left the scene, Shaan is the best among the current lot of singers in this genre..
If u look at the range of the voice, then KK is the best among the present lot (plus he has a fantastic voice quality too)..
For high pitch stuff, Sukhwinder , rahat fateh ali khan etc are there..
For classical stuff. shankar, Shafquat amanat ali khan etc are there..
May be u wont agree with some of the singers that i put in each category, but the point i m trying to make is that if u are comparing 2 singers, compare in a genre..tat would be a true comparison..Hope u get the point 😉