I have used several switchers [Samlex, Astron, DuraComm, & MFJ], & they all work great. Some might generate rx noise on HF, but not on VHF, or UHF. On my equipment, XPR4550, it draws more current in analog, than digital. Low power in analog draws 7 amps, while in digital, only 4 amps. A 15 amp supply should be fine, as it would be a rare occasion one would xmit on 2 radios at the same time.