The heated mattress is only about 150 watts (about the output of a large light bulb). It doesn't "get hot" like an electric blanket. It mainly keeps the chill out. It works very well at that in hybrids. We used it in our Roo all the time. We have not camped in cold weather yet with our Mini Lite. Our pass-through/folded down sofa is under our mattress. Not QUITE the same as full outside air like in a hybrid, but somewhat better. So I can't yet comment on it's use in a Mini/Micro Lite.
1988 Coleman Sequoia - popup (1987-2007)
2012 Roo19 - hybid (2012-2015)
2016 Mini Lite 2503S - tt (2015 - ???)
2011 Traverse LT, 3.6L, FWD
2009 Silverado Ext Cab, 5.3L, 4x4, 3.73
2016 Silverado 2500HD Dbl Cab, 6.0L 4x4, 4.10