i don't disagree with them being really strong or top tiers, I just don't think Saturn, who's old enough he has to carry a cane everywhere, is stronger than prime Garp(who's top 3-1 marines of all time).
Also Oldbeard and Garp were still handling Admirals even when they got wounded.
Don't let their old age fool you. They still had my boy Sabo hauling ass out of their chamber when they transformed, even though Sabo wasn't scared of Issho or BB before.