I disagree that he has been very good.
IMO, he is the weakest link on that OL and that's not good when he was the shining addition this year. His PFF grade is well below average for OT's (it's worse than Spencer Brown which is surprising, but it's PFF so there's a boulder of salt there.)
Rashee Rice is currently 61st in the NFL in receiving yards. He's a bright spot in an underwhelming WR group. Again, IMO, but that Chiefs receiving group is even worse this year and they were nothing special last year.