I realize that this is an old and continuing subject of debate in the industry, but I am interested in the current updated consensus on the topic. Specifically, what kind of PCBA cleanliness level should be reasonably expected to achieve? 

Of course the answer is always "it depends," because that is the reality. And the actual acceptance or control level needs to be set according to product requirements. But what I am after is slightly different: What level of cleanliness would you expect to be readily achieved by a good quality manufacturing process under normal circumstances?

Some general parameters to narrow down the question:

- Measurement technique bulk solvent (ROSE per IPC TM-650 2.2.25)
- Pretty normal PCBA design - 0403 components, some through hole, nothing really unusual
- Pretty normal process, RoHS, no-clean.
- Class 2 PCBA, but high impedance low current battery powered application
- High production volume (>1 million units annually)

I am not aware of anything that has replaced the 1.56/cm^2 "standard." but this has been around forever, it seems. Common sense tells me that even if a formal standard has not changed general performance might have improved, on account of smaller components, tighter board spacing and general technological improvements. 

What has been your actual experience in this regard?

Thanks in advance,
Steve