I've had one for years and love it so much that I now have two of them. When I bought mine (when they first came out) there was only one style so I can't comment on the differences or how much more helpful the newer ones would be. If I were to buy one today, knowing what I know now, I would GO FOR THE GOLD and buy the best one I could afford.
They are very handy on the table saw (when cutting narrow strips especially) and the router table for control of small items. Just remember, saw blades and router bits don't really care what they cut and plastic is no problem for them.
However replacement parts are available for them. DAMHIK.
Rog
