He KO'd Fitch in the first round. It took GSP 5 rounds to beat Fitch and he never had Fitch in danger of being finished.
Hendricks has more stoppage wins in the last year than GSP has in the last 4 years.
GSP definitely had Fitch in danger of stoppage a couple of times.
As for finishes, totally irrelevant to who is the better fighter. What does Hendricks do that Koscheck doesn't? Nothing and he has the same chance of beating GSP that Kos did, very little.