Vibrates at low speed
Your review: I had this same model fan before, and it was excellent for years. Replaced it today with the new one. It's slightly out of balance, vibrating at low speeds then smoothing out at higher speeds. I presume it's a QC issue.
Pros: Great CFM in a small, easy-to-mount package. Relatively quiet.
Cons: This particular unit vibrates at low speeds. (I have installed it with vibration mounts--it's a balance issue.)