I had a Heart (n/k/a Xantrex) inverter for ten years on a previous boat and sold it. Only problem was more our fault than there's, but they replaced the unit without a fuss.) We sold the boat, I presume the unit is still going strong.

We've had another Heart/Xantrex unit (modified sine wave, inverter charger) for eleven years without incident. It's going strong.

Maybe things have changed, but they seem pretty good. Some of there units have 2 year warranties -- and some have extended 10 year warranties on their "green power" units. (I'm not sure about the marine models.)

What were the circumstances of your problems, Neil?