I'd like the Chiefs over the 9ers. Purdy is a couple of DBs dropping easy INTs from watching at home. They easily could have lost both of their previous playoff games. Really both of their opponents gave it back to them.
Andy is a great coach and Mahomes is unlikely to make those same mistakes.
I don't mess with the spread.
As for the GOAT conversation, wins are not a QB stat. They are on the field less than half of the time. I let my eyes tell me who is better. I look for ability to lift a team and make avg pass catchers look good. Systems can make QBs look better than they are, too. Brady changed teams, but the system and his buddies came with him. Not so much a stat guy, though great QBs will have some good stats. They can also be deceiving. A good team that is ahead will typically pass less than a team that is behind. Except the Pat's who tended to keep passing. INTs are not all created equal either. Hit the WR in the hands and he muffs it into a DBs hands? A team down 10+ late in game and the QB forces it in? There's a great QB out there with lots of INTs. Some were of the knucklehead variety. Other times he'd force it in for game winning TDs 5 times and get picked off once but people focus on the INTs.