LightForce 170, or 240?

[Schattenjager]

Just about to order the Light Force's for the ARB. I have several 170 lens' from previous sets, so it would save a little money to stay with them. However, I have ample room for the 240's and am wondering if there is much practical difference in the two? At first I thought the size difference was just for installation ease, but they make handhelds in the same sizes. Has anyone used both? Do the 240s simply make for a wider pattern? Pros / Cons of each?

Thanks!