Hi stbwolfe,
Thanks for the feedback on your mattress … I appreciate it 
It sounds to me like the mattress is working well for you and you are “in the middle” of your two main sleeping positions (back and side) which is usually the indication of a good choice.
The most reliable way to know if a mattress is working well for you is any specific symptoms you are having. In general there are “alignment” symptoms (typically discomfort or pain in specific areas of the body) and “pressure relief” symptoms (typically numbness, tingling, or pain on specific pressure points). The rest are mostly preference issues or based on “feel” which is less important and is often part of adjusting to a new sleeping system. When you find yourself describing your experience with “it feels like” (with things such as how far some areas of your body are sinking in) then these are usually preference issues while if your descriptions are more in line with “I have” (discomfort or pain or sore spots etc) then these are actual “symptoms” that may need to be addressed. Sometimes different symptoms may not be connected to a mattress mattress and may have more to do with the events or changing circumstances of your day or week and how you feel in general.
A sore spot in your hips may be a pressure point from a mattress that is a little too firm (although for men pressure points are more typically in the shoulder area) or it could be from a mattress that is a little too soft where the hip joints are not in their neutral alignment over the course of the night (usually from side sleeping) which can lead to some tension and discomfort in the hips if you sleep in the position that causes this for too long. Pain in the midback can come from either a mattress that is too firm and puts direct pressure on the muscles or from a mattress that is a little bit too soft and your back is sinking in unevenly and the muscles are working to keep your spine in alignment instead of fully relaxing. Upper body pain can also come from a pillow issue (where a pillow is too thick when you sleep on your back and it pushes your head forward which can cause neck and midback issues. Post #2 here may also be helpful when you have a new memory foam mattress to help you identify other possible causes for any discomfort. There is also a list of forum posts that talk about the various symptoms that are most common with a new mattress purchase and some of the possible solutions in post #2 here.
Identifying the underlying cause of any symptoms on a mattress can take some detective work but the first step is always a more detailed conversation with the retailer or manufacturer you purchased it from. They know more about their mattresses than anyone and the better ones will be very helpful in making suggestions if you are experiencing any issues with your mattress.
Phoenix
.