Your biggest concern should be battery life. The engine may be hard to start at those temperatures, but it will run fine if you can get it started. Putting a few drops of fuel down the glow plug hole and then turning the propeller over by hand a few times will help lubricate the piston a bit and help it turn over a little easier than just cold cranking it.

Your transmitter and receiver batteries will be much less efficient than normal in that kind of temperature range, however. You would be doing your self a favor to recharge your Rx pack after every 15 minutes or so in the air.

The mylar covering, regardless of brand, will also likely be more brittle at these temperatures. A botched landing or otherwise minor incident with the plane could result in a major recovering project.

Good luck, and good flying!