i had go for alen brand due to the test and reviews i found in the internet. nowadays, if the product got no reviews or testimony by those who had use is basically a marketing gimmick.
I didn't get Sharp or Honeywell in the end is because they lack the information and they don't stack up.

I can understand why Sharp not revealing any of the information to the public. It's because they use a lot of TV advert to brainwash couple with mass production price to lower the price.

Why I love Alen?
It came with Lifetime Warranty. That's confidence . Typical American built product , always lasting and confident.

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While we and others see the value in having the secondary feature of an Ionizer (where low levels of negative ions improve health ranging from respiratory allergy relief to reduction of headaches), we have the option to turn ours on or off to satisfy this while SHARP's is automatic to support their patented technology!
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Scientific evidence clearly shows that a hepa filter is the best choice and there is no scientific evidence showing the benefits of an ionizer yet there is a lot of evidence that demonstrates the harmful effects if this is the primary technology being used.
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At this point, if you are unable to agree with what has been stated, compared or produced scientifically or independantly, may I suggest we agree to disagree and move on and let those on the LYN decide for themselves.