I have the 735 and the dewalt dust cover and hose. I use it with an old garbage can and a bag. The fabric is supposed to breathe a bit but I do not think its enough in that the pressure is so high that the dust shavings gets between the cover and the trash can as well as into the can. Taking the cover off then dumps a large amount that then has to get cleaned up by hand. The Dewalt solution is better then none and since space is limited it works for me, for now. I also do not use it a lot but it sure comes handy when needed.
I'm guessing using a Lawnmover bag would be similar except that the dust shavings will be captured in the bag and not a garbage can. Those Lawnmover bags are tiny especially if you need to tighten them around a hose, so I would expect you to empty it after a few boards. Planers tend to produce quite a bit of shavings. If I had better space I'd get a dust collector with a decent size bucket.
Its ok dust wise though I try to run this outside only.