Martin thank-you so much for all your amazing work, I'm in awe of the time you're able to set-aside to help the community!

Coming back to this for the 1st time in months, only just been advised by a local retailer (aust) I pre-ordered with, that my AP-15's are available.
Apparently they've been ready to pick-up for many weeks!

I plan to read this latest round in it's entirety tomorrow, but as it's now 320am I must get some shut-eye.
Just wondering if anyone can summarise, is the AP-15 still considered the noise/CFM king, or is there a new contender or contenders?

How does the 2150 & 3000 RPM compare to the 1850, are either a better alternative IYO?
Perhaps the 2150 is not a substantive enough improvement over the 1850?

I have some AP-15's ordered as rad fans, but if the CFM to noise ratio of the 2150 or 3000 is as good, & one can still make them comparatively quiet (as needed)...
...then perhaps they're a better option?

Any thoughts/experiences greatly appreciated, thanks/night!