Which is better for running an RV air conditioner?

The FlexPower 4500ies. Its 4500 peak watts and 30A RV receptacle handle a typical 13,500 BTU RV air conditioner's startup surge better than the Generac's 3500 peak watts.

Which runs longer on a tank?

The Generac IQ3500. It runs 8.9 hours at half load on 2.60 gallons. FlexPower does not publish a run time for its 7 L tank.

Is the Generac worth the extra $79?

Yes if you want the LCD, the longer run time and the 3-year warranty. No if you need maximum watts, an RV outlet or easier lifting.

FlexPower rates the 4500ies under 63 dB. Generac calls the IQ3500 ultra quiet and uses two engine speeds to cut noise, but does not publish a dB figure in the listing.

Can I parallel two units?

Both are parallel ready. Generac sells a parallel kit (#7668) separately for two IQ3500s. FlexPower lists parallel capability but not the kit details.

Which is easier to move?

The FlexPower. At 82 lb with a telescoping handle and built-in wheels it is 27 lb lighter than the 109 lb Generac.

FlexPower 4500ies Quiet Inverter Generator with Electric Start vs Generac iQ3500 Inverter Generator

Buy the FlexPower 4500ies if you want more running watts, more outlets and less weight for less money. Buy the Generac IQ3500 if you want a longer half-load run time, a digital display and a 3-year limited warranty. As of November 5, 2026, the FlexPower is $849.00 at FactoryPure and the Generac is $928.00 at FactoryPure, so the FlexPower costs about $79 less.

Today the FlexPower 4500ies Quiet Inverter Generator with Electric Start costs $79.00 less at its best price.

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