Refubished Units
I bought a Uniden refurb years ago. Came to me w/the same problem that it was probably returned for originally. The external power supply turned out to have a cold solder joint. Since it was external, it didn't hurt anything to try to fix. I I spent an hour and about 25 cents in solder,electricity and tape. The external power supply case wasn't pretty when I was done. However its been running day and night for over 10 years.
I have also purchased from the Whistler scratch and dent a couple of times. Some items still had the plastic over the display. Another shows minor issues which I think can be polished out.The actual performance has appeared to me as good as new.
The first purchase took a little longer to ship because they waited to send my refurb item w/my upgraded 668. The second purchase was within the 2-3 day priority ship time.
The previous poster explains the Whistler policy very well.
All that to say...
Most of us that have been around go by the following. If it works the first time you plug it in it should be OK. Run electronics 24/7 for 30 days when possible. If it works for that long, unless it experiences a surge or accident, its going to be good for a long time. If it should fail in that short period, you are well within any warranty.
Your experience will certainly vary. IMO, if you know what you want, its a very good way to buy.