You guys are making me want to try this out soon...and Im sure I will!

That said,how much starter do you add to your dough mix when making new dough?
I've seen anywhere from 5% to 30% Total Flour....depends on your available ferment time and more specifically the fermentation temps!
Is the flavor a night and day difference over an IDY or ADY dough that fermented for an entire day or cold rise 2-3 days in the fridge?
Depends on the Starter used...I know I can dicern a difference between my Ischia (thanks Norma) starter and the one I created from a dough given to me by a local pizza shop.
Whats the best way to use this stuff? Cold rise or room rise?
I've found that a rise for 12 hours at 60-65
o to be optimum, followed by 2-4 hours at room temp, that being from 72-78
o....
Will NY style doughs benefit from starters or are they ideal for higher temp ovens an neo style pies?
I've been making what I consider some of the best crusts of my pizza making life using an 11 year-old oven, a 1.25" soapstone and no oven tricks. Not trying to be coy, but definitions aside, it's all a matter of taste. I dabble in poker and playing styles are very much a matter of personality. Regardless, the best make what works for them, work for them.
That said, I think most people would say that the addition of a "starter" to a "NY pie" would change your product...you wouldn't have a "NY pie" any longer. I'm not quite sure how I'd classify what I'm currently making but it isn't NY and it isn't Neapolitan....guess it's Neo Neo

So to answer your question, yes...I think it could benefit

I have read alot about starters,but still unsure about the exact applications on how to use it best. 
At some point you just have to dive in, that's what I did. This is one of those things you have to see and feel for yourself. There's only so much reading can do for you. This is a living, growing being that you have you nurture and feed at least weekly but the payoffs in my opinion are immense...that is, depending on your end goals.
I'm not that type of person that defines pizza...if I'm in Chicago, can I enjoy a deep-dish pie? Of course? When I'm in CA, do I dabble in a supple dough seafood pie, you betcha! When in St Louis I even enjoy cheeses beyond mozzarella...if you ask me to make a pie, I'm making what I like and for me, that includes a starter and cool temp ferments

Mark