Premier line is assymetric, Master is symmetric that's the main difference. Ball reactions are different. Dimension more arcy in my opinion. Have not seen a 2d yet, but you can read the reviews. Don't know how many you're looking for your arsenal. You could build your arsenal w/a combo of those, but you'll need something for lighter volumes from elsewhere. Master has only 2 balls & both lines are basically all hooking balls on oil. But, I wouldn't limit yourself. VG & Dimension are pretty good balls, but that just covers the heavy. Gravity & 2D cover med to med heavy. Nothing in those 2 lines cover the very light. I can play my regular Shift on lighter volumes, but that's just me. If you can get your hands on one I'd highly recommend it. I can play it on almost all volumes and have success. The super heavy is about the only condition it may not be good on, but everyone is different.
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"The last time I saw a mouth like that, it had a hook in it."
Rodney Dangerfield