Outer Limits 4x4 Board

I own a 2004 GUIII 3.0 Patrol. I recently fitted 285/75 16 A/ts and consider the vehicle needs a bit more clearance without the expense of new springs. I am considering 30mm coil spacers. I would appreciate to hear from anyone who has experience with these spacers, both pros and cons.

Cons only from me.
Main thing is when compressed to the bumpstops the springs will probably be at bind and will fail quicker.

Bazzle

also at full flex wouldnt the spacer fall out if the coil comes loose?