I have an older Elna 634 mechanical serger that I love. It has color-coded threading and cards which show and tell how to set up for each stitch. It has 2-3-4 threads and an easy rolled hem feature. No cover or wave. It is very easy to use and runs so smoothly. I see many women who have fancy machines that are so complicated to use, they spend most of the class-time getting set up. I think my model is no longer made, but I have seen similar ones at the dealer. This one works for me on doll clothes, pillowcases, skirts, capris, napkins and placemats. For me, a good basic machine is very good enough. JMHO.