So what is the point of lifting it that much and installing 35/37" tires?
Well, if you have to ask....
Actually, the point is all about ground clearance. Late model IFS/IRS Rovers have pretty good clearance stock, but if you really want to push things you'll run out of break-over in a hurry.
So the stock air bags are capable of six inches of lift from the factory? Does the cross link air suspension function in terms of down travel? I am not trying to argue, but I'm completely confused . I heard directly from LR that the bags didn't allow for this much lift so I'm anxiously awaiting pics and detailed info.
I hate to speculate without more details, but then again that's what the interwebz is all about so...
He didn't say if he's using the stock struts, or just the stock bags from the struts. It's possible they've modified the struts but are still using the stock bags. At $10K, I'm guessing there is a fair amount of custom hardware going on - I'd expect fabricated longer control arms since lifting a Rover that much would significantly reduce the track. At the same time, some sort of mod to the struts to lengthen them and retain the correct angles. You would also need longer axles to accommodate the longer control arms. It could be done such that you retain the stock ride height adjustments, just with all of them raised significantly. We already do some things like this when running rods and bump stop spacers such as the Proud Rhino kit for the LR3/4/RRS.
However I have not worked on a '15 like this, so I'm not sure what the limitations of the stock hardware are. I'm basing my theory on the LR3/4/RRS designs and what I would do if I had $10K and a willing fabricator to work on my suspension.