re: ONEIDA - Dust Sentry.

I've had mine since I purchased my supercell and it works quite well.  The adjuster thingy (technical term) on top of the sensor is key to ensuring the light isn't going off when the drum is empty or not going off until it is too full.  When I empty the drum, the first thing I do is take the sensor off the top of the lid and wipe the dust off the sensor on the bottom.  Then it goes back into the hole when the lid is put back on the drum until the next time the drum is full.  Once you get the sensitivity dialed in it is very reliable.