YES! More crud gets stuck under the rim of a drop-in sink. If the undermount sink is sealed properly when installed there should never be a problem.

For top mounted sinks, if sealed right it shall also not collect crud. But in my experience, not all sealers will work FOREVER and FOREVER. Had to reseal top mounted sink after 15 years. If you fore go checking the seal then water will seep in and become trapped--> mold, rotting of wood counter, uplifting of formica off the wood.

I think over mount sinks are worse. Try this...



Have your countertop material project out about a quarter of an inch from your undermount sink. This way the seam where crud usually collects is covered. See pictures for this detail. Hope that helps. Charmean