I've been doing some reading on these and cant seem to find any definitive information on what the actual changes are other than increased sustain...
the key part that I want to know is will it dull/brighten the sound how is low end affected.
Also does it affect the amount you can pull up as theyre pretty damn huge so I can imagine there being some cavity wall contact
I've found that it brightens the tone significantly. I didn't notice much of a change in the low end, except for it being a bit tighter due to the brightness.
I put a 37mm which is quite a bit longer than the stock one on my FRS and it gives enough room to pull up.
Takes up quite a bit of room, but still plenty to pull up. It hasn't inhibited me whatsoever.