I have a Janome 6600 and love it. The only problem for me is that the manual instructions are not exact all the time (especially the letter embroidery part which even shows a different set up on the machine than mine has!). But otherwise I love it. I quilt all my quilts myself and once I did a quilt with quilted pieces already on it, so my machine had to go through up to 3 layers of batting and 4 layers of fabric and it worked like a dream. So did DH who held the far end of it and went right or left, according to my head movements, with the whole shebang while I stitched!!!!
About oiling: I was told also to only oil by putting a drop of oil onto the pad under the bobbin (I bought an oiler that looks like a vacination needle and have been using it for years). But we live in the country a long ways from a repairman and he worked with DH and me on how to oil it in general. Basically, take off the front piece and oil into the holes that seem to be oil places, and on shafts that move where they touch another part; and remove the bottom piece and do the same there. BUT always clean (he sold us a little $15 dollar kit that connects to the end of a vacumn tube) BEFORE you oil, then oil. Be sure to have your needle raising bar down so you don't put the weight of the machine on it! If you have a repairman near by, you might want to skip the oiling/cleaning and have him do it. Don't you love the way they tell you to change your needle every so many hours of use, or oil your machine after so many hours of use, or get it cleaned after every so many hours???? How on earth do you keep track of those things!!!!
I love the big throat of this machine! The letter part is my only gripe (and for me, that's something)
Happy sewing!