Njmurvin, It's a learning curve. You're in the right place to get much information... much of it conflicting! Colder is a "relative term"! Handling cool weather is the summation of your preparedness and your RV's ability. Go to an Artic Fox forum, and "pick their brains", on winter camping... what are the approximate limits and what they specifically do for the "colder" temperatures. We're not AF experts, but 10 F should be pretty easy.
The water supply (hose) will probably be your greatest challenge. Heat tape and insulation will take care of some pretty low temps. Of course, the campground must have heat taped,insulated,frost free faucets for your supply if the weather is pretty cold for a lengthly period. We lived in our 5 er full time through 2 winters ( while building our home) seeing quite a few minus 30's and colder. As mentioned...you will use quite a bit of propane. If you are going to do fairly long term camping, get an extra pair of 40#er's. Buys you more time to get your refills done. If your going to full time it for a long period of time in one location....consider a large rental tank ( example: 250 gallon) from a propane service company. It's much cheaper per gallon for your refills. As heat rises, put insulated "pillows" ( can be purchased) in your vent (Fantastic Fan) opening. This will stop a lot of heat loss. Windows are another "huge" source of heat loss. A roll of foil type insulation can be cut to fit, and placed on windows not important for your "viewing pleasure"! It could even be added to the inside of your basement cargo doors for added insulation. And of course, make sure all of your access door(s) have good gaskets. None of this should be necessary, if your only seeing the low 20's.
Don't worry, you've got a pretty good cool weather unit...you'll be fine!
We like winter camping....it opens a whole new world of experiences!