I have 4 Donner receivers, 2 with batteries, 2 without. The power switch on one of the battery powered ones has gone unreliable. It can take several presses for it to change state. Even when it is powered externally it needs to be switched on, so the iffy switch is still a problem. The ones without a battery don't have a switch. My advice is that if you don't need the battery option don't go that route. Also, it doesn't hurt to have an extra if going wired is problematic.
Despite this issue, I'd still buy more Donner units should the need arise. Mine are 3 or 4 years old now. Batteries still last all night.