I had a dixie chopper for 12 years, one of the best mowers i have ever owned for flat out cutting. I had a trac vac on it and it worked, but...
I now own several John deere z's. They are by far the best bagging mower I have owned or used in my 30 years of mowing. I downsized my bagging machines to a 54" deck because I felt that a 60" was too much deck for any collection system to handle volume wise. It was a very good choice on my part because I am seeing far better results in both productivity and quality of cut. BTW I also have the mulch on demand deck on another J.D. and again, it also is one of the best cutting/ mulching mowers I have used.