Well, Mickey did say they were looking for an extra bobbin case for the 201 to make adjusting the bobbin tension easier - so I thought maybe they found something that was easily interchangeable for the 201. Like Rodney says, I also can't see where changeing out part of the 201 would be easier than adjusting the tension on what is in the machine to start with.
With my LA quilting machine, setting bobbin tension is a normal step of the process for each thread type used. I considered getting the TOWA gauge, but didn't. I did get a trigger pull gauge to see how that would work, but I think that will go in DH's tools as I did not find it all that helpful.