He wasn't a closer, so that hurts when comparing, but to me, the numbers that count the most are WHIP or OPS against and K rate/ BB rate (I like K/BB that covers both) show them very close.
In my previous comp, I left off the first years of both and took away Uehara's last year. Here are their full career numbers:
You said the rest of Koji's career, he was "good," but I think he was much more than good for a long time (7 years).
OPS Against
.485 Kim (.476 Late & Close)
.588 Koji (.566 Late & Close)
WHIP
0.890 Koji
0.920 Kim
K/BB
7.33 Koji
4.23 Kim
K/9
14.7 Kim
10.7 Koji
BB/9
1.5 Koji
3.5 Kim
ERA+
211 Kim
162 Koji
Post Season WHIP- K/9
0.833- 10.5
1.258- 2.1
Save%
91% Kim (333/372)
84% (95/113) Koji
IS%
19% (15/77)
26% (27/105)
I think it's closer than it might seem.
I have no beef with anyone saying Kimbrel is better, but it's close, and I think Uehara was more than just good outside of 2013.