I have a smooth, pin down Match Solid that's great for getting the idea of how lanes are going to play at new houses or on sport patterns. By definition, it's my benchmark.
However, I bowl all of my leagues and usually practice at a single house where pin downs are 10 pin machines for me. So 90% of my bowling (everything outside of tournaments and an occasional practice session elsewhere) is done without even having my "benchmark" ball in my bag. Which begs the question, is it really my benchmark? I know what works there, start with my medium ball of the ones I bring (Double thumbed Radical Jackpot) and ball up or down from that ball.
So yes, I can see how people may have different benchmarks for different purposes. In my case, I have a tournament benchmark and a league benchmark. Each ball's purposes are well understood by me, so it doesn't really matter what label you put on them.