Obviously MSW inverters are not built to the same standards from company to company. I have both types of inverters in our rig and our LED tvs, HD sat receivers, Blu-ray player and Bose system can't tell the difference in terms of their overall performance. We did run our microwave convection a few times off our MSW unit but as a precautionary practice use our genny to power it now.
With the prices of true (or pure) sinewave inverters coming down to reasonable prices last couple of years it would be wise to go that route, read reviews to eliminate problematic brands as they too are not all built to the same quality standards.