I have a 6000i, too, and love it! I use it much more than my other machine that I paid 5 times more for! It is just a great all around machine. The only thing I can say is a negative with the brother machines is the bobbin cover..that little plastic piece that covers the bobbin...I find it a pain to remove, it just seems like overkill, when every other brand of machine out there has a simple cover that's easily removed, I need to use a tool, (screwdriver or scissors, seamripper, whatever is handy) to get in that little space to loosen the latch. Not a big deal, I've adapted..especially since I love everything else about the machine...but I do not like the bobbin plate!
On the other hand, it is very easy to use and so quiet!