Well for one I was going to have them ano my cocker at the same time and two I've never installed one of these and would rather have it professionally installed. I would just feel better about it.
Have you tried installing one yet? If so, then can you give some details about it? If not, then how do you know how easy it is to install? I'm just saying that just because a company claims their product is idiot proof doesn't mean that we idiots wont find a way to screw it up.