How reliable and exact are police composite sketches?

Depends on how accurate the description was i suppose. The more details given and the deeper the description the better chance the picture will look similar to the accused. But the likelihood of a photographic comparison is not realistic.

This should be in general.

Some are amazing!

They really don’t use this unless the person can absolutely say for certain that “this is what they look like”..my guess is that the police are expecting it to be very reliable.

I actually recently read an article that said police sketches are incredibly inaccurate.

Highly accurate judging by this masterpiece!!
I mean, that narrows the suspects down a bit :¬(

They vary widely by the quality of the artist, the success of the victim at recalling details and conveying the image in their head to the artist.