Are you certain the Samil inverter only had a 2 year warranty? I can't recall another inverter with less than 5 years.
Samils currently have 5 years at Segen but I'm sure there was a phase when they offered 10 years as standard.
If there's no shading and the inverter's been specced correctly, I'd say a Samil is a decent choice. Although, if the customer has lost faith, it may be time for a change.
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