I have the bagger and use it with both mulching and the stock JD blades. I am impressed with its performance. Dumping the bags is very easy. So far I have not clogged the chute. Putting the bagger on the back of the tractor is simple. Can easily be done in less than a minute. The chute? thats another story..
I have found that the chute is a real pain to attach to the deck. Just does not seem to be a good fit. You really have to muscle it into position. To be honest at first I thought I had the wrong chute. Dealer came out and said that it was the right chute just tough to put on. He said over time it will be easier as the plastic molds a bit. I do not use it that often so I doubt that will happen. Still I can get it on in 2-3 minutes with some aggravation.
A few tricks I learned - have the deck in the lowest setting. Put the chute into the bagger first, and make sure you check the deck level afterwards. For me sometimes my pulling and pushing gets the deck out of whack.
When using it, the left side bag fills much quicker than the other. As air flow gets restricted the right bag will fill. I am kind of thinking of modifying the chute within the bagger to deflect more grass to the right bag so they load evenly.
Let us know what you think if you get it.