No need for a pure sine inverter - waste of money.
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Motors apparently live longer on a Pure Sine (or close digital approximation) Wave.
Radios are happier, especially if a capacitance is added.
Modified (Pseudo) Sine Wave inverters lack (except for powering incandescent lamps and simple electric heaters).
Yeah my computers worked, but later needed new power supplies (yeah, I know backup computer PS's are mostly "modified" sine wave "providers".)