>Due to the thin-ness of the upstairs mattress, I'm thinking of
supplementing it with a Thermorest mattress. 

In the days of old, I wore camoflauge and parachutes and lived on a
thermorest.  It's perfect for hiking or military use as it beats everything
else IN ITS SIZE.  However, it's prolly not going to improve your Westy
mattresses. 

I agree with the others, foam would prolly be better.  

Or perhaps one of those real thick airmattresses available at Wally World. 
They're blue and covered with velour on one side.  About $30.  Various sizes. 
Takes forever to blow up (12v hairdryer or mini compressor?) but REAL comfy. 

Many blessings,
Ray

der Kapitan     IXOYE
Huntington, Westy Virginia
Recovering Sniveling Technophobe Lurker and Co-inventor of the Internet

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