Hager,
I don't use both drivers but here are some answers to your questions.
Q1: Specification looks the same, just a matter of preference. I prefer the separate boards for the same reason you have.
Q3: They both have it. It's used to limit the current to your motors.
Q4: Theoretically, 10 microsteps give you better resolution compared to 8 microstep.
Q6: PIC16F84 is a microcontroller. It is a chip that can be programmed to do what you want. In this case, it's converting step/dir signal to signals required to drive the LMD18245. Xylotex may do it differently, possibly with other chips.
Q7: Both drivers works on step/dir signals. As long as your software support Step/Dir signals (and most do), you're okay.
Q8: Breakout board simplify wirings. Again, it's a matter of personal preference.
I didn't check the detailed spec of both drivers, that's why no Q2 & Q5 above
Regards,
Stupid questions make me smarter...
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