There are other things that do not like MSW inverters, did not know that some things didn't like them and cooked an older makita battery charger. The newer makita chargers don't seem to have this problem.

http://www.donrowe.com/inverters/inverter_faq.html#modified

And click on,

Do I need Modified Sine Wave, or Pure Sine Wave?

for a list of devices that don't like MSW inverters.