A bit of false advertising, but I thought I'd provide results from my weatherized MS16A modules. These were upgraded with silicon and installed 1 year ago. After a few months they stopped working. Usually that happens because they are corroded and destroyed. I decided to replace the setup with different equipment, so this is what they look like before trashing.
The screen is cracked and disintegrated when touched. No noticable evidence of water inside. No corrosion of contacts. In fact, I powered them up with 3v on bench top power supply and the LED's flashed so I suspect they still work.
IOW, careful application of silicon on all seams and fastener holes CAN significantly improve the survivability of sensors in direct weather. However, it will not actually make a difference as the screen is apparently not UV resistant and will ultimately be the failure mode. I have another sensor I will be pulling today that was not exposed to direct weather or UV and its lasted several years even with allowing batteries to corrode inside.
