We have had the 213 B+ since March, and I got to thinkin about whether we should winterize the RV here in Baton Rouge, where we typically encounter only a few nites where the temp stays below 32 for more than 5 or 6 hours (a hard freeze) all winter.
I can't tell you what to do, but here is our experience.
We live in Northern Minnesota. We've already had it get to the high 20's when our unit wasn't winterized. We did get ours winterized this week, but it isn't crucial for us to do it until we know that it will be in the teens for a long time. Typically, we get at least two weeks of -30º, so we want it winterized before then, of course.
Water expands, obviously, so you want to make sure that the pipes don't freeze and crack. Around here, 32º isn't considered anything out of the ordinary, and if our temps hovered around the 30º's, we wouldn't do a thing. We've never winterized our units until the high temps were in the 30's, so we're early this year. If I lived where you do, I wouldn't winterize--but I am absolutely not giving you advice, only mentioning what we do. :)
PS--we had water (black, fresh & gray) when it hit the high 20's.