Thanks again for taking the time to test the valves! We finally have a reference for how working DISA valves are supposed to behave during the INPA test. Now we know that the motors in the valves can also fail and that solid flaps are not sufficient proof of working valves.
In my case, I purchased a used 3IM with original BMW valves 11617560537 and 11617560538. Both small and large valves would only close partially during the INPA test:
Without any reference, I believed this was just how the INPA test worked until I immediately got fault code 2AAC for a faulty motor in the small valve. I suspect that oil intrusion damages the motors as there was a significant amount of oil in my valves. In hindsight, I would buy a used bare manifold but new DISA valves with the money saved by using a BimmerLabs tune.
With that said, performance still felt decent with my faulty valves but definitely not as much improvement as I originally expected. Slightly faster in low to mid RPMs while the same or less in high RPMs. I suspect performance will vary greatly depending on how your valves fail. I will update on how new valves perform once I've replaced them.
To test the valves with INPA, go to Engine > your DME (eg MSV80.0) > F6 (Activate) > F1 (Actuator Activations 1) > Shift+F6 (VIMDISA). I believe you should return control to the DME (F3) afterwards.
You can test the large DISA valve without removing the intake manifold:
Update:
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.