You’re lucky the 530 has a magneto ignition. The 630 has electronic ignition with variable timing and over-rev protection. That’s why they’re so much more expensive. My thought was that it should have a control unit but it’s inside the coils.
I would have replaced them sooner had they not been $160 each. The cost of the coils is outrageous in my opinion. I was considering swapping out with a Kawasaki, but now that it's fixed I'm once again happy with the Honda. So your coils lasted about 700 hours for each set, that's pretty good...