I have a 99 and a 201, and they are both nice machines. I like the full size of my 201, and it's in a small table which means it very pratcial for maneuvering larger pieces of fabric. The 201 has revers stitch lever, and can lower the feed dogs. All 201s have the same features, even if the later ones look a bit different they work the same way. It's a very smooth running machine. Internally it has tree sets of meshing gears, and a rotary hook. It will stay smooth even if you floor the pedal, the only thing that gets louder is the needle punching through the fabric. The aluminium version 201K23 is noticeably lighter. I have both version, in a cabinet you will not think much of it, but in a portable bent wood case or a suit case type model you will notice the weight difference. The 201 originally came with a darning / embroidery foot. It's often missing in the accessory box, but this model works well with several of the modern low shank jumping feet. The 99 didn't come with any foot for this purpose, but a spring to hold the thread in place. You have to choose darning foot carefully for the 99, because the presser foot bar is a bit shorter and act up with some of the new ones. The 99, 66 and the older version 15 uses a feed dog cover, because the feed dogs cannot be lowered. The 15s with the stitch length lever can have the feed dogs lowered. I've been reading Helen Howes advice on buying a machine and think her suggestion of starting with a round bobbin machine is a good one. She specifically mentioned the 15, 66, 99, 201 & 185 but I'm struggling to get a grip on how these machines compare, their strengths and weaknesses that would help me know if one or other models would be the more desirable or best fit for me.