Hi srockrae,
All wool toppers will compress to some degree (typically about 30% over time) but shifting and compression will depend on the type and breed and coarseness/resilience of the wool fibers, the type of layering methods, the thickness of the topper, the compression and tufting of the wool, the size of the wool batts, and on various other factors as well. Once the wool has gone through it’s initial compression then it will maintain it’s resilience and feel over the longer term without significant ongoing compression. There are some suggestions here that will help to even out compression and shifting and avoid or reduce the “hills and valleys” in a wool topper.
Wool products can be difficult to compare in terms of “value” because there are many variables that can affect the price of a wool topper besides just the amount of wool that is used including the country of origin and whether fair wages and prices are being paid to the wool producers, the farming methods and growing conditions of the sheep, the type of carding, cleaning, and scouring that is used, the addition of any lower quality fibers to a wool topper, the type and breed of the wool, the specific construction of the topper and the amount of time and hand labor it takes to layer and tuft the topper, the type of outer fabric that is used in the topper, any organic certifications, and other factors as well. There is more about organic certifications in post #2 here and in post #2 here.
It can certainly be tempting to try and make “raw material” comparisons based only on the amount of wool or the thickness of a topper and this can certainly be one valid means of comparison but by itself it can be misleading.
When you can’t test a particular topper in person then the best source of information about a particular wool topper will be a conversation with a knowledgeable and experienced manufacturer/retailer that can help you differentiate the specifics of the topper you are considering and help you make more meaningful comparisons with other “similar” wool toppers. The suppliers on the list will tend to be open, transparent, and informative about the wool toppers that they make or sell and the information they provide you can help you make more informed choices between the many options you have available. I would agree with you though that while OMI (Organicpedic) products (including their wool toppers) are certainly high quality … they also tend to be more costly than other similar products.
There are a number of wool manufacturers that have a similar program that can recard the wool in your topper and add any additional wool that is needed and then recover it for a reduced price. I think it’s a good idea.
There are other natural “hair” fibers that would be “somewhat” similar (horsehair, angora, alpaca etc.) many of them are more costly than wool. There are also other synthetic fiber toppers that are cheaper but none of them will have the same feel or properties or durability of wool (or other natural fibers). For those that prefer the feel and performance of wool or other natural fibers (and there are many) … nothing else will be the same.
Phoenix