I'll use darn near any excuse to buy a new tool, but why in the heck would you need a durometer? Are you going to test the hardness of each tip before you install it? Seems a bit overkill to me.
Almost every tip on the market already has a hardness rating. Of course you can't take their posted hardness ratings as gospel because there are flaws in the raw material and the manufacturing process itself.
However, I put a good amount of faith in the posted hardness ratings, and here's why: If a company puts out a new tip and claims the hardness to be 75, they are vying for the business of all players who like to play with a 75. Once a bunch of players try the new 75, if it's harder or softer than they prefer, they won't buy another. The only thing that travels around faster than good news is bad news!
My two cents worth: don't bother buying the durometer and stand. Buy a different toy!