I taught in a DR with a Thomas Duplex. When I had to replace the filters I decided to move to a Kodak Utility 10x12 OC safelight with optional Red safelight over the trays and a few small OC lights in deep corners. Each station had a Jr Lab red safelight. Avoiding noise was a benefit. In a home DR the Duplex would be overkill; too bright and too loud.