Benefits of an expansion leaf pack?

Im looking at an Icon Stage 2 Suspension Sytem (coilovers and shocks included) and the only difference between the stage 1 and stage 2 beside the extra $200, is that the stage 2 comes with an expansion leaf pack... what are the benefits of an expansion pack and is it worth the extra $200?

 

I know there’s a few guys that’ve done it, let me try to think who it was. If it were me, I’d much rather just buy RXT leafs. Have heard conflicting stories on how the expansion pack holds up to weight and off-road use.

 

I have the icon expansion pack on my Pro. It’s doing okay, but i consider it a great 1/2 measure, until I can afford a complete custom leaf setup from Alcan or someone else. Because of the constant static load I’m carrying, around 1,100lb, I need a set with substantial preload.
But, for around $260 vs $950 +/-, it’s alright for now.
With the pack plus the CB shackles, I’m setting about 2” higher in the rear than stock. Springs are pretty flat, but if you look at the brand new truck springs, they are pretty flat too.