The conclusion is OP-1 is worth every dollar spent. Versatile and capable of end-to-end tasks without doubts. For those who haven’t got enough experience creating drum patterns, it is a little bit challenging to find the right beat using the sequencer, but buying OP-1 is indeed buying its limitations which makes you focus on every beat.
I bounced 4 tracks and use Logic Pro for some simple mixing and mastering. But I am quite satisfied with the result as I am not experienced enough.
The only issue I got is very wiered: some bars just loss some notes which makes it not aligned, leading to the system crash. A little bit annoying as I just used it for several hours.
My unboxing and my first try: