what's the difference ?

I know I read this somewhere before...

one style is suited for 1 type of stroke....

heel is more for gated stroke, and center for sbst or pils stroke???

thoughts

you are correct

Usually, one see face balanced = sbst and toe hang putter = arc stroke

But there are always exceptions to the general rule - arc guys can also play face balanced putters.

As to center shaft with toe hang, one might feel less release in an arc stroke, while generally you'll feel more release in an heel shafted toe hang putter. It depends on what works for you. I play both with an arc stroke.