What kind of towing capacity are you after, and what is your budget, if you don't mind me asking? There are probably other choices that will fit your needs better than an Edge. If you tow often, even smaller loads, then I'd recommend something based on a RWD platform. Like a previous generation Explorer, a Durango, a Tahoe or Yukon, etc.
We tow up to 1,500 pounds occasionally with both of our vehicles, and they do it, but they're not optimized for it. If towing was a larger part of our "vehicular lifestyle", then I'd trade one of them for something with RWD.