https://forums.macrumors.com/thread...mpared-to-recent-airs-and-pros-chart.1969613/
The thread above compared m3,5 and 7 to a core i5 MacBook air. You can see that the m7 is quite noticeably faster than the i5. I haven't compared the benchmarks of the i7 but if you know the relative improvements of the i7 over the i5, that should give you some idea as to the m7 vs i7. That said, benchmarks may not reflect real world usage.
I think the awesome thing about Core M processors is that they consume very low power and turbo-boosts if needed (until they run hot). That's why they can keep up their speed with the Core i variants in tasks that requires speed for a short period of time. If you do sustained heavy loads, then the laptop runs hot and throttles. So if your workflow requires heavy sustained workloads, then the Core M probably isn't a good idea.
One thing not mentioned is the ability to charge the MacBook with a mobile phone power bank. You can't use this on the MacBook Air obviously (no USB C). I'm not sure if you have factored this in, but in my experience, having a power bank present to charge my phones and the MacBook is a huge advantage.
Using a regular 2.4A, 5V power bank, my MacBook charges
while simultaneously using it for low powered tasks. On the new MacBook Pros, the higher power consumption means even for the same task, the same power bank will not be able to keep up with the power consumption.
