I need some advice on rotary cutters because the Fiskers i've been using just isnt cutting it (no pun intended..lol) I've gone through 3 in the last 6 mths. The nut and screw seem to not stay tight after using for a mth or so. Then the blade wobbles...very frustrating and i'm recovering from hand surgery so something maybe ergonmically correct might be better but not to much money?? Any suggestions would be Great!! Thank you in advance :D