How stiff are 404's?

I spent the morning searching old posts and couldn’t find a good answer, but the Tale of Two Tires was an interesting read.

I’m a clydesdale and I’m rubbing my Ritchie DS wheels on my brake pads on hard climbs. They’re great on the flats, but I worry the flexing will take it’s toll.

I know ‘stiff’ can be subjective, but would the 404’s be a good choice for me, strength wise? I’m 220ish, with a goal of 210.

Very stiff - or you can get the 404 Clyd. wheel…

I saw those, and I am leaning towards them since I seem to be a human durability test.

I’m big, but I love climbing, obviously I wouldn’t train on these, but knowing they won’t be bouncing off brake pads when I’m already lugging 220 pounds up a grade would be helpful.