An update after almost a week with the aspirator. First off, I never had the issue with temp spikes on my original WS-1400-IP station, nor have seen such with the Osprey, as the early/late sun rays are blocked due to houses, but I had seen what appeared to be stagnant air heating when the winds would die off (typically not an issue here). I have found that I can spot when the aspirator powers up and down each day, not by any significant change in the temp per say, but by the smoothness of the reported temp changes. The aspirator kicks in when the solar reading on the Osprey is around 150-200w/sq meter which is about what I would expect given that the aspirator solar panels are only about 2" sq. I spotted this smoothing of the temp curve almost immediately on installation, but it took a few days for me to decide it was for real.
This is leading me to the conclusion, that a 7X24 aspirator would be preferable. To that end, I have designed a solar charged super cap design that will run the aspirator for several days without solar re-charging. Also in the design is a fan-failure detector circuit, also powered by the super caps, that will give me a visual indication if the aspirator fan should be in a lock rotor state. I am going to mount the system down pole so as to give me access should such be needed. I will be maintaining the aspirator mounted solar panels as they will typically pick up the load quicker than the solar array associated with my super cap setup.
I want to stress that the aspirator did NOT make any material improvement in the overall temp trend line, but it DOES improve the reading-to-reading smoothness across time. Even with a moderate breeze, the OEM solar rad shield by itself is resulting in some minor stagnation of airflow around the temp sensor based on what I am seeing. As to how well this little aspirator might handle early/late day temp spikes is open to speculation, but I would say that it would reduce them at the very least.
Given the relative simplicity of the aspirator I deployed, I am hoping that it sparks some interest at Fine Offset to offer something similar as an add-on accessory.