A friend got one of the units you mentioned, not sure which model but apparently one is "non-standard POE" and can actually run from 12VDC. My 3220 is true POE with a third-party 12-to48V converter. I'm happy with mine, works well and provides WiFi coverage for iPods and such all over the boat in many anchorages.
Yes, boat projects tend to experience scope creep. This spring's projects were to upgrade my transom shower to hot/cold, and rewire my AC entry (to put the breaker before the inverter/charger and remove excess wire), which involved emptying the cockpit floor liferaft locker and removing some panels.
Now, I find myself refinishing, epoxying and redrilling screw holes, and repainting those panels and a few more. None of which was on my pre-launch list.
1998 Jeanneau SO45.2