Ditto what @marcspaz said. And, I'd ask, what is your use case? Do you have a portable you want more power output from? Are you talking simplex to one station, or many? Are you using a repeater? Another thing to consider is the receiver. If you hook up a cheap radio, with a low quality receiver, to a 50 watt amp you will have a giant alligator... Big mouth, tiny ears. You will probably not hear 1/2 the people responding to you, and the half you do hear, you would probably hear without the amp. Honestly, if you really need the power, you would probably be better off looking for a good quality 40 or 50 watt mobile radio. Personally, I would look at a used piece of commercial equipment - you will get a much better receiver than any mass-market Part95 certified radio. . You will easily find plenty of Part-90 radios, and if you care about certification, Part-95 radios are also available. This topic is commonly addressed on the MyGMRS forum. Search through the threads for Kenwood, Icom, Motorola, and Vertex to see what might work for you.