Tonight I am settling in and staying warm in the Winnebago. I am in a campground outside of (chilly) Fort Lauderdale, Florida.
This campground, like most campgrounds, advertises that wi-fi Internet access is available. The claim is accurate, or at least somewhat accurate. There seems to be a wi-fi hotspot in or very near the main campground office building and store. However, it is a large campground and the signal doesn't cover the entire campground. I haven't yet experimented by walking around and measuring signal strength. However, I am camped about 200 feet from the main building and I only see a very weak wi-fi signal. It is so slow as to only be marginally useful.
Luckily, I have a Sprint 4G/3G wireless card. I powered up the aircard, waited a few seconds, and it immediately connected to Sprint at 4G speeds. In short, it seems to work as fast as any hard-wired Internet connection I have used in the past. I now am not using the campground's wi-fi signal.
Lesson learned: don't depend on campground wi-fi. If you are serious about getting work done and also checking email, bring your own access. Obviously, that won't work at all campgrounds, especially those out in the boondocks, but it will work in many places that otherwise do not have reliable wi-fi connections.