I don't know anything about the first one (although it is "pretty") but the 15-91 is a nice machine. You can drop the feed dogs if you want to free motion quilt and assuming it just needs oiling or tweaking, it is a workhorse of a machine. Apparently most of those older machines need rewiring due to age. But then again, I could use some "rewiring" on myself personally due to age so I cannot fault an older machine that needs it done also.