i plan to get an air purifier to put in my room and baby's room. any suggestions on brands/models? looking for something that is not too noisy, and energy efficient. i was looking into get the whirlpool whispure which was the highest rated air purifier on consumer reports, but couldn't find this model on the hong kong whirlpool website. also was wondering, which is more effective at removing air particles and pollutants - ionic or HEPA?