WOW! Sorry I just saw your post and I am a little late. As for the 2nd AC, I would say save your money. I have the same unit and only 1 AC, never had any issues keeping my camper cool and for a while the front 2 vents weren't working properly.
I guess if you are in the south it's different. I am not.
As for the Mattress, im pretty sure this is THE most comfortable RV mattress out there. My wife likes it as much as the one in our house!
Good luck!
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2014 Ram Big Horn CC 1500 tow package, 3.92 gears.
2016 Crossroads ST270BH (June 18, 2015)
(2015: 7 nights camping, 425 miles) (lost track and became too lazy to update!)
- LED lighting throughout
- Power jacks/levelers
- Maxxair covers for the roof vents
- Black tank flush connection
- Hot water heater by-pass
Some units come with some or all of the above. I know these are minor options but they are nice-to-have options that may be available or that you can negotiate in with the deal. I was fortunate that my unit had every option installed.