This spring I'm putting the fsport staggered 19" wheels on my 2013 350GS AWD. I'm trying to decide if I should put 15mm spacers on the front and 20mm spacers on the rear. I have little to no experience with spacers. Please give me your thoughts...

 

Up to you .. it's purely aesthetics.

 

It won't have a negative effect on the AWD system? Can someone recommend a reputable place to get them from?

 

Will I have to get longer bolts?

 

Not for 15mm or 20mm thickness. They will mount to existing lug bolts and have additional pressed in lugs to mount your wheels to.

 

Car handles different with spacers.

 

Technically yes, but I'm not sure about how much different on the street? I didn't do a head to head comparison.

 

steering seemed a little tighter and rode smoother.

 

Spend the money and get the good stuff. http://www.trakplus.com