2 nuts or 3 nuts, which is better?

[gps100proof]

So as i'm looking to upgrade a Jt500, I notice there are two kinds of locking nuts. R2 and R3. What is the difference, what would a jackson kelly and dinky normally have, and does changing the nut make as much difference as say uprading the saddles?

[rjohnstone]

Big difference between the two.
R2 is 41.3mm wide with a 10" radius
R3 is 42.85mm wide with a 12" radius

Most Jacksons come with an R3 (or equivalent).
The JT500 comes with an R3 equivalent, but it has a shorter profile.
If you put an OFR R3 on there, you'll have to shave down the nut shelf a bit or the strings will be to high.