I received my new DISA valves and installed them. Here are the comparison videos:
Large DISA - faulty motor, BMW (Mahle) 11617560537:
Large DISA - brand new, BMW (Mahle) 11617579114:
Small DISA - faulty motor (code 2AAC), BMW (Mahle) 11617560538:
Small DISA - brand new, BMW (Mahle) 11617560538:
The replacement took about 2.5-3.0 hours. I'll report back on performance after more seat time.
Update: Much better performance with the new DISA valves! Power delivery is buttery smooth and consistent throughout the entire power band. I've also started breaking traction under acceleration more often. I have the BimmerLabs 330i software for reference.