Better at run blocking. He can push the pile or pull or get out in front and steam roll the second level. Will probably remind Rams of Roger Saffold.
He was the 3rd string center so he has some position versatility.
He had a few series last year where guys blew past him but has otherwise been very reliable in pass protection.
As others have mentioned, recent injury history is what likely kept the Lions from keeping him on an already expensive Oline.
A bit expensive but assuming good health, he should be an upgrade to the Rams run game aspirations.
B+ signing with a high floor and decent ceiling.