Lets see some pics fellas!!! (just aftermarket, we can all see the stock chromes at the dealer )
I know there are some riding 20's!!!
Is Possible to stuff 21's 22's maybe with the new 22" tire they made for the CL500?

do they require crazy offsets? Can you stagger them?

 

There are hardly any options yet to really go aftermarket on the RL. The Bolt pattrn and offset is strangely unique, hence many manufacturers haven't made wheels to accomadate the RL.
Maybe in a year or so you might see some better options. but as of right now we have stock 17"s, OEM 18", and a few selects from Tire rack as posted recently.

 

if the bolt patterns and offset are weird, you should just try going with custom wheels like iforged or HRE. They can accomodate all bolt patterns and offsets

 

The only thing I can say here is to keep the sidewall on all the tires the same or it will put a lot of stress on the 4wd system.

People say staggered setups for 4wd machines put a lot of stress on the 4wd system but I have no expirience with this.