I have a Park spoke length gauge, but I have to say that I was not all that impressed with it and went back to using my Starrett 12" rule. Basically I measure one spoke (twice) and mark it with a small file then use it to transfer a mark to another flat surface (usually my table saw). Once that is set up, it's pretty easy to measure and mark the rest. I have a Hozan tool, which I bought so I could use up all (hundreds) of the spokes that I have accumulated over the years. I like the tool but to cut and thread 72 spokes for a new set of wheels is a bit of a chore.
Good luck.