I have seen been a part of many generators installs and prefer a transfer panel. A decent electrician should put one in for relatively little cost, especially if you can work ahead of him and cut out the access he requires. Try to narrow it down to just the wiring for him. I had a guy give me a price of under 100 one time, plus the panel of course, but find a place like CES or Grainger and that should be around 200. Home Depot is good for certain items, most things I can find a better deal on somewhere. Like any other purchase, find out where the pros are shopping and always ask if there is a discount. Military, senior citizen (many of our members here...), LEO, anything.
As to backfeed, what I have heard is not only the danger of a linesman being hit, which is minimal when your backfeed is 220V and they are supposed to be smarter than to ground themselves out, but it complicates the job of finding the outage when they are getting volts from a place where there aren't any. That can piss them off proper and when they track it down you will get a knock on the door and an angry, wet, cold, tired, hungry, hairy gentleman.