These are a little better than some cheaper models if used properly could last a long time sometimes its a little slow to start up probably trying to find mppt then works good i purchased this unit through another site it did not do well at all i hooked it up to 3160 watt solar panels for a total of 480 watts theyre wired in parallel at first it put out about 150 watts in full sun i got that reading using my killawatt meter about 2 minutes later it tripped my gfi plug but continued to show wattage on the killawatt meter meaning it was still running so the anti island feature was not working i had already pulled the plug so it should have turned off but it did not finally a few seconds later it we