Who uses a power inverter with their laptop?

I've had my new laptop for a few weeks now and occasionally run it off a power inverter. I bought one to spec with the laptop's power block so I'm not worried about that, I'm just not positive about how clean the power is coming from my vehicles electrical systems. I drive an 05 Corolla and an 06 Chevy Express van. I haven't had any problems or weird smells or anything, I'm just curious if anybody HAS had problems. Personally I love having it as an option. Power was out for almost 5 hours last night in +/- 90 degree heat. The girlfriend and II sat in the air conditioned car watching Devil's Rejects.