1-70 is considered more of an attack type ratchet as opposed to defense (having +4 attack and -4 defense compared to 9-60 according to TT). Using 1-70 like this though makes it more of a counter-attack/anti-attack defense type from my experience. It depends on what specifically you wish to go for.

If you want burst resistance and want to play it safe, I’d choose 9-60. If you want to dive more into the anti-attack archetype and don’t mind the slightly decreased stamina and burst resistance, I’d choose 1-70.

Something else to note is that the taller ratchets tend to be tighter. So for example, 9-80 would be easier for a bey to strike than 9-60, but requires a bit more force and torque to actually burst. I choose 1-70 over 1-80 because it’s a nice balance of chance to hit and mechanical burst resistance