Sam Rinzel (6/25/2004): 6'3.25 at Combine, listed as 6'4.
Ethan Del Mastro (1/15/2003): No Combine in 2021, but Del Mastro is also listed at 6'4.
Age 19 Season:
Rinzel: Number 6 Defenseman for USA in the 2024 World Juniors (Gold Medal) as a 19 year old. 2023-24 All-Big Ten Second Team (behind 2nd round pick Seamus Casey and soon to be 2nd overall pick Artyom Levshunov, alongside 3nd team with 2nd round pick Ryan Chesley and Super Senior Scooter Brickley. Also Big-Ten All Freshman Team alongside Levshunov)
Del Mastro: Top 3 shutdown role for Canada in the 2023 World Juniors (Gold Medal) as a 19 year old. 2022-23 Second Team OHL All-Star Team (behind Top 10 picks, Pavel Mintyukov and Brandt Clarke, alongside 2nd team with 1st Round Pick Logan Mailloux)
Age 20 Season:
Rinzel: Going back to Minnesota for another year of NCAA, TBD.
Del Mastro: 2023-24 AHL All-Star. Good offensive production and a +14 in a pro league.
I don't really see anything to suggest Del Mastro is behind, let alone significantly, compared to Rinzel as they are only a draft year and hockey birth year apart. The only edge I give to Rinzel is handedness scarcity.