re: Weber Spirit Rotisserie feed back? Worth it?

Yeah if you don't have a dedicated rear mounted rotisserie burner or multiple burners that you can configure for indirect heat, then you'd want to have the burners on low and a drip pan directly underneath. There's also the clearance from the spit to the grill grate to consider. You may have to remove the grate altogether if the clearance isn't high enough - thus eliminating somewhere to put the drip pan and likely causing flare-ups, which should def be avoided.

Here's a good thread about it: LINK