Some will depend on what you are addressing/ what your goal is.
Yes, I tools with grip can kick it up a gear.
Both sizes of the battlestar are excellent and kick things up a level.

I have not used a muscletrac. I recommend the little battlestar.
If you have never used a tool like this before and are new to doing mobility work I would start with the muscletrac and upgrade to the littlebattle star when you are ready for more.