Basically, you can use anything that will give you results.
Why should there be anything wrong with M43?
This thread might interest you, although it is a bit long:
Accuracy and speed. I’m impressed.
There are quite a few examples with different cameras, most not very expensive.
The results are still very good.
From those, you can draw your own conclusions for your specific case.
Bottom line is (for me at least) you don’t have to throw a ton of money at your camera dealer, only if you need to squeeze the last tenth percent of accuracy out of it.