I sent two messages on allergy cosmos website which remained unanswered after two weeks asking for advice on which i.q. Air appliance to buy to remove benzyne, formaldehyde and other voc's from my home. Due to the current vogue of suburbanites burning wood in their stoves my local air quality is terrible. I bought 5 x i.q. Air pro plus purifiers, £(4,500) plus the new small bedroom device personal zone protector, and their air quality home monitor only to find out that the i.q. Pro plus 250 doesn't make your home totally safe airwise at all, since it doesn't screen toxic gases in wood-smoke from the air, just particles 2.5. I simply wanted someone at allergy cosmos to advise me which of their products would top-up my already considerable investment in home air quality equipment. The layout of the on-line site is amateurish with a tiny little box at the bottom for one to submit their question and when you do submit a comment it, out the blue, it promptly tips you out of the thread. Allergy cosmos products are excellent, but the on-line support, and presentation of it's slightly baffling site is disappointing when you consider that their returns, filter-ordering procedures and telephone one-to-one contact is, I've found, so excellent. Could someone at allergy cosmos please enter their on-line staff workroom and wake everybody up. 24th October 2018 I was delighted to receive a telephone response to my original review above from chris, one if the testers, i believe, from allergy cosmos. The health pro plus was the correct choice (5 of them) i made to cope with the mass stupidity of neighbours heating their home by burning wood. The middle classes have given up smoking in public places for health, so now it is okay to poison the air with seriously damaging wood smoke. I digress I have changed my rating from 0 stars to five stars for the products themselves. I bought an i.q. Air quality monitor and it is marvellous to watch the particulate level in my home fall from a dangerous 200 to the level of zero within 10 minutes of putting my iq health pro's on (just 2 of them) at a maximum 6. I recommend anyone suffering from neighbours' indifference to poisoning the air to buy a health pro plus 250 and simultaneously, an iq air quality monitor. The 2 really belong together, and help to save filter life as it is easier to gauge the necessity of putting the purifiers on and at what speed to deal with pollution levels in the home. Having said my piece about these life saving, sanity saving, purifiers i also must add that it is not acceptable for a quality company like allergy cosmos to allow the chat service to be as hit and miss as it is. The comprehensive explanation i received today from chris could have been avoided entirely if the on-line chat staff could be TRAINED to cover for one another during staff absences and ensure that all their customers seeking advice are able to receive that advice promptly. However, thank you chris, and i wholeheartedly endorse the iq health pro plus 250 as the absolute best in the world.