I have a Janome MC4900QC - the QC is for quilter's choice. It sews a lot faster than most of the other machines that are at my Saturday Sew-In that I hold once a month or so. I can finish 3 things in the time it takes a friend of mine to do 2 - her and I used to sew together all the time and I'd make sure I had busy work to keep me busy until she caught up lol. I'm going to miss her terribly after she moves away when her house sells :(
My machine doesn't have the longer throat. I wish it did. It would have been sweet.
When I was buying that machine, the dealer was trying to convince me to get the 9" throated machine. I didn't only because it didn't have the free arm which I really needed for other projects.
The 4900 is a great machine but ridiculously over priced. I wanted lots of fancy stitches and I have to say that I have barely ever used ANY of them!! Hindsight - buy the cheaper machine, buy the feet, save some money lol. Well. I treated myself. I wouldn't trade it for anything now :)