Entei and Darmanitan live in different contexts. Darmanitan's 95 makes it slower than most non defensive pokemon in OU, it suffers from the recoil it has to receive with its main move and its bulk is lackluster, while Entei's 100 makes it one of the fastest mons in UU, coupled with excellent bulk for the combination of speed and power. I would argue that their counterplay is also different, as Darma's is more offensive (it's stronger but slower and more susceptible to priority) and Entei's is defensive.
If you simply wanted raw damage, Arcanine can get very very similar numbers to Entei, but it's clear that Arcanine doesn't need a discussion.
I'm not sure about the statistics as those are not sufficient, but we can't get more detailed information.
Entei does not need sun to be stupid, but sun makes it even dumber.
Also just saying, Flygon needs chip to ohko entei