What degree is the incline of this wedge? I talked with a health Researcher, He believes 30 degree would be good. I want to keep my pillow though

I purchased the larger 33"D x 12"H x 30.5"W and the angle is about 20 degrees lying down and 70 degrees sitting upright. The 25"D x 12"H x 24"W angle is about 26 degrees lying down and 64 degrees sitting upright. The 33"D x 7.5"H x 30.5"W angle is about 13 degrees lying down and 77 degrees sitting upright.

Is it non-allergenic?

Polyethylene of the package is very smelly - ether-like smell, so I just did order next day delivery & unpacked shipment very quickly & did throw away-outdoors that stinky wrap,- expedited next day delivery also has got this pillow's foam the full possibility to regain its original shape & size in ~ 1 hour in compare with 2 days delivery (- in 3 days; I'd 3 different delivery-times - first one was longer than 2 days because 2 business days included week-ends, - then my first two pillows' "memory" foam did only partially regained their shape & size (~1/2) to approx. half of original size in about 3 days - so I did put two pillows in one case - so the "doubled" pillow has approx. the original size of one pillow & works fine & also the longer than 2 days delivery time did take about 5 days to ventilate away the ether-like smell from package-wrap when I put pillows & their cases separately close to my powerful HEPA & activated-carbon-filter air-purifier - for these 5 days my kitchen was very smelly - I didn't at first recognize that this ether-like smell's source was from polyethylene wrap which should be thrown away outdoors as soon as possible,- these guys who wrapped these pillows with stinky polyethylene are either idiots or hate their customers. Probably before been wrapped these pillows were non-allergenic but after - definitely not. After I ventilated the next-day-delivered pillow long enough the small practically disappeared & it's probably non-allergenic again but I'm not a judge to say that. So be aware to have over-night delivery & to unpack smelly wrap & throw wrap outdoors-away as soon as possible - the longer the pillow & polyethylene wrap are together the harder & longer you have to ventilate pillow & its case separately near HEPA+Carbon-filter-air-purifier. My last experience with next day delivery I could rate as 4 stars to this pillow in condition to take all precautions to get rid of smell & for pillow to regain original shape & size.

is the cover a dust mite free cover?

Actually, memory foam does not support the growth of dust mites. I am not sure if dust mites can live in foam but I tend to think they cannot. I have serious issues with asthma, but have not had a problem using this product. You must launder the cover weekly in hot water. I am asking if they will sell additional covers for just this reason.

Since this doesn't have a washable pillow case, how do you clean it when it gets dark with body oil?

It does have a pillow case, but I didn't think it looked very durable, so I use a bath towel over it. (we have cats and I was afraid that they would claw up the pillow case and it would disintegrate when washed. I was unwilling to test it, so I went the conservative route of extra protection).