Since you don't already have the Action Packed I would pass cause you already have a ton of stuff to cover mediums.
This is based on what I have seen of them.
Infinite will handle most any heavy condition you will find and if it isn't moving nothing else is going to either at the same surface prep.
Paradigm good on med/hvy with clean backends or med with slight carrydown can get squirty on higher levels of carrydown.
Vapor Zone good for mediums handles carrydown fairly well.
Crossfire nice control piece for med/lt.
Radical no experience but based on the vids at b'wick.com and their description good for mediums very strong in the backend on med/hvy maybe a bit hard to control on this, absolutely kills it on medium.
I think that you have a ton of overlap on mediums and no true med/hvy or lt ball.
A nice compliment to the Infinite would be the Big One with the surface around 1000-1500 sheen/smooth.
A step below the Crossfire - Desert Heat
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