I knew that Denver mattress was going to be trouble from the get go. We never even slept on it. I purchased a 11" Brentwood memory gel mattress (full queen) on Amazon for $475, but I see that right now it's on sale for $399. We had one in our previous trailer and loved it, so I knew what I was getting.
Make sure you order the correct size. My old trailer required an RV 'short' queen (60x75"), but my 2016 Jay Flight uses a standard queen (60x80"). I believe Jayco uses both sizes depending on the model trailer you have.