I have mattress issues primarily because I weigh 350lbs. The foam mattresses that come with the X20E simply do not work for me. So I end up putting a couple of sleeping bags on top of it, a 1" memory foam and still I would feel like I'm sleeping on concrete.
On our last trip I decided to go to Walmart and found these things:
http://www.walmart.com/ip/Norsk-Stor...-Gray/13253268
They actually helped to cushion the bed enough for me to feel comfortable at night. Simply lock them together, slide under the mattress and Bob's your uncle. Add Sleeping bags for additional padding, LOL.
For $20 bucks it works for me and made my recent 12 night trip much better but I am still on the lookout for a good deal on a topper when and if it comes my way.
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Wayne, Kim, Mallory & Abby the Dog
2013 - Jayco Jayfeather - X20E
2012 - Toyota Tacoma DBLCB Sr5 with towing package
Equalizer 10k WD, Prodigy P3 Controller, TST TPMS
2012 - Jayco Sport 10 Popup - Traded