To answer your question, only if you have ever had a squib, then you will use it all the time. And no I have never had a squib but yes I do use one.
Let me explain, every and I mean every rifle cartrage gets weighed for the last 8 years (over 20,000). With the last purchase of another AR, I needed to find a faster way to load my 223s. I had the solution, a Lee Classic Turret press, but did not feel comfortable just dropping powder and going on to the next step (yes I trust my powder measure) but this isn't about trust, it is about NEVER making a mistake.
So out comes the check book and in comes the Powder Check Die. Now I load away and KNOW that the charge is correct.
Catching one SINGLE short charge will more than pay for the cost of the Powder Check Die (guns are expensive.)
Only you can tell if you need one or not.
Black die on the right is the Powder Check Die.