per 100 possessons -
Noel: 21.4 points, 13.9 rb, 2.4 A, 3.1 Sts, 2.4 Blk, 6.3 F
119 ORtg 102 DRtg
Holmes: 23.0 points, 12.8 rb, 2.3 A, 1.7 Sts, 2.4 Blk. 5.8 F,
118 ORtg, 105 DRtg
Not a huge gap between them, Noel is a more polished defensive player, in all aspects, Holmes has more offensive skills. I think Holmes has more upside b/c Noel really doesn't have a shot, he's improved out to 10" but only if left alone. Holmes spent more time in college but was badly coached, he's still learning how to block out and play fundamental defense, and to become more consistent with his 3 point shot (up to 33%). He has the right coach to teach him, which is a big positive.
Both have inflated stats b/c they came off the bench most of the season against inferior personnel. Both are best suited to a rotation role where they don't have to match up against top starting centers. Both are excellent in that role, but their high rate of fouls suggests they'd struggle to stay on the floor for 30+ minutes against starters.
Neither is good enough to carry a team like Embiid, but paired with another center with complementary skills, they could be part of a championship team. If Embiid can stay healthy, Holmes would be a perfect backup for 15-20 minutes a night.