I've been using this for light to medium duty at work and haven't had a problem with it after 4 months. Then again, it can break at any time.
You'd be paying a 1/5th of the cost of the scanner approximately and that doesn't seem worth it. You could just get a new one when it dies. And besides, you're covered under the manufacturer warranty and Amazon's return policy for a while as well. I'd pass personally.
I have only had this newer version for about 1 month now. I also purchased the previous version a year ago and have not experienced any problems with it. Me personally, I would not purchase the protection plan. Usually as with all items , it breaks when the warranty has expired :( Hope this helps your decision.