Hi pressurepts,
Unfortunately there is never a “good” time to make these types of decisions and as I mentioned in the sticky topic here about terminating their membership … at some point the elastic stretches too much and “breaks”.
There isn’t much I can add to my comments in this and the other topic about what you “should” do but if you do decide to try a different topper then I would make sure that you have enough time to try it out to make sure that it works for you and to make sure that you would be able to return the mattress and the topper (and have this in writing) if the combination doesn’t work out as well as you hoped for. I would also keep in mind that if a different topper doesn’t work out you may also be in a similar situation where getting a timely refund may be difficult or delayed.
As far as other memory foam options … I believe that you are in the Bay area and if this is the case then the better options or possibilities that I’m aware of in your area that you can test in person before a purchase (subject to making sure that any mattress you are considering meets the quality/value guidelines here) are listed in post #2 here. If you are still primarily focused on memory foam then a trip to Nest Bedding may be worthwhile since they have both memory foam mattresses and memory foam/pocket coil hybrids.
If you are still considering other online memory foam options then the mattress shopping tutorial includes a link to a list of some of the better online memory foam options I’m aware of (in the optional online step) which would also be well worth considering.
I would also keep in mind that there are no “standard” definitions or consensus of opinions for firmness ratings and different manufacturers can rate their mattresses very differently than others so a mattress that one manufacturer rates as being a specific firmness could be rated very differently by another manufacturer. Different people can also have very different perceptions of firmness and softness compared to others as well and a mattress that feels firm for one person can feel like “medium” for someone else or even “soft” for someone else (or vice versa) depending on their body type, sleeping style, physiology, their frame of reference based on what they are used to, and their individual sensitivity and perceptions. There are also different types of firmness and softness that different people may be sensitive to that can affect how they “rate” a mattress as well (see post #15 here) so different people can also have very different opinions on how two mattresses compare in terms of firmness and some people may rate one mattress as being firmer than another and someone else may rate them the other way around. This is all relative and very subjective and is as much an art as a science.
When you can’t test a mattress in person then the most reliable source of guidance is always a more detailed conversation with a knowledgeable and experienced retailer or manufacturer that has your best interests at heart and who can help “talk you through” the specifics of their mattresses and the properties and “feel” of the materials they are using (fast or slow response, resilience, firmness etc) and the options they have available that may be the best “match” for you based on the information you provide them, any local testing you have done or mattresses you have slept on and liked or other mattresses you are considering that they are familiar with, and the “averages” of other customers that are similar to you. They will know more about “matching” their specific mattress designs and firmness levels to different body types, sleeping positions, and preferences (or to other memory foam mattresses that they are familiar with such as Tempurpedic) than anyone else.
Phoenix