Odd as it may seem, I tend to prefer the un-numbered tension dials: on both my Featherweight and my new-to-me 401G, I have to use a dreadfully low or high tension number to achieve a perfect stitch despite all my attemps to tune it with videos for help (in my Featherweight original manual, the previous owner made a note "normal sewing = tension number 7" I know it's not really important but it tends to irk me so having an old style un-numbered tension unit gives me more freedom imho. Anyway, since it's always best to make a sample before tackling on your project, having a dial numbered tension unit or having a plain one makes little difference