Hi yoshirider,
Just in case you haven’t already … I would make sure you’ve read the mattress shopping tutorial which has all the basic information, steps, and guidelines that can help you make the best possible choices.
In the optional “online” step there is a link to some of the better online memory foam retailers and manufacturers for memory foam mattresses (which you may already have read as well since both Select Foam and Christeli are included).
If you have done some careful and objective testing using the testing guidelines in the tutorial post and are confident that the Tempurpedic Rhapsody Luxe is the best “match” for you out of all the local mattresses you have tested (or out of the Tempurpedic lineup) then several of the manufacturers/retailers that are listed there make a mattress that uses the Rhapsody Luxe as a reference point including … Select Foam, Christeli, and Brooklyn Bedding. Most of the others that specialize in memory foam mattresses would also be familiar with the Tempurpedic lineup and would also be able to provide you with good guidance about which of their mattresses would be closest to the Rhapsody Luxe or would have the best chance of being a suitable choice for you. There is also more about the different ways that one mattress can “match” another one in post #9 here that may be helpful.
When you can’t test a specific mattress in person then the best way to decide whether a mattress would be a suitable choice for you would be based on a more detailed conversation on the phone with each of the manufacturers you are considering. This is one of the most important parts of any online purchase. Since an online purchase can be riskier than a local purchase that you can test ahead of time … the options you have after a purchase to exchange or return a mattress and any costs involved may also be a more important part of your decision and the “value” of a purchase. This can help you decide whether a purchase is inside your range of “risk tolerance” just in case your sleeping experience indicates that your mattress isn’t as suitable for you as you hoped.
Once you have narrowed down your options to choices between “good and good” (mattresses that you believe are a good match for you and that use good quality materials that have no weak links) and you are at the point where there are no clear winners between your finalists then your final choice (see here) would be based on how you feel about your conversations with each of them and your “best judgement” based on all the parts of your personal value equation that are most important to you.
Phoenix