Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Samlex SEC 1223 Power Supply

It's compact and quiet. It's RF filtered, which is often important in switching power supplies. Some have complained of RF noise. Not me. I have used mine for several years with a high-end HF transceiver. Check eham.net for additional reviews. The big proplem I have with the Amazon listing is the price ($174.95 or something like that). This unit routinely retails for only $99.95, with sale prices about $10 less.