I tend to do like the military and standardize and buy spares. I actually have a spare wave in my truck now because I loaned my wave and it almost got lost and I didn't want to be without it. I also have all three squirts and need a to replace a small pair of wise-grips that were stolen so a crunch is on on my want list now.
I don't like the rivited tools though, I think they could make quite a market selling user customizeable tools and a wide assortment of blades. People like me would have to buy each blade and won't be able to decide which to carry and end up buying three tool bodies to carry all the different blades in <img src="images/graemlins/smile.gif" alt="" />