We purchased a SleepEZ 10000 last February. King.  I have configured F/M/S/XF  and hubby is S/M/F/XF.  I have lower back problems, 2 surgeries, and on my old S mattress my back was hurting most mornings.  I have virtually eliminated my back pain.  My hubby has no issues and hasn't even wanted to  switch his configuration and I've changed mine a few times the first couple of months.  However........I have noticed that each of our sides have slight dips and when I roll to the middle where the latex meets, I feel a slight hump.  I did not think latex was supposed to develop this dip.  We have new box springs, not slatted.  My hubby and I both sleep good, but the slight dip concerns me.  Any thoughts?

I don't think that latex is completely immune to developing impressions but you should definitely be talking to SleepEz about this.