I'm not sure the springs are different between the two. However, the electronically controlled shocks available on 3.0 Q's certainly make a difference. I haven't heard of anyone making a swap, so it'd probably take some knowledgeable research to find where the controller goes, and of course how to install, plumb, and program everything.

FWIW, an unexpected benefit of installing the H&R/Bilstein setup on my SQ was improved ride quality over stock. Might be something to consider if it's a showstopper.

You don't mention what tires & wheels you're running. Tires with more sidewall - which could include swapping 21's for 20's - is probably the easiest path to follow. What psi are you currently running? That can have a noticeable impact as well. If you're not already there, dropping to the mid 30's range will help.