I feel that I should chime in here as a tribute thingy myself.
Of course the music has to be good and sound like the band but in the case of the Police, they sounded rockier live than the records and a bit different depending on the era of their live shows.
It has been said that I look a bit like Sting, so that does actually add to the show.
I've also studied how he moves on stage and was given the greatest compliment by Billy Kulke (Letz Zep) when he said, you've really nailed that Sting thing.
We use the correct instruments (replicas) and I always try to wear an appropriate outfit, depending on what bass I'm using.
I saw Wrong Jovi and they did the lookalike thing really well, Ritchie was a touch short but musically they were spot on.
Horses for courses of course but the punters do like to see a look a like (I think they do)