I've run the Maifield setup on indoor, high-bite bluegroove (large track); Indoor slick-groove/moderate bite small/tight track; and a larger outdoor dusty clay track.
It works everywhere.
I used to run standard offset wheels and the truck was always sketchy and on edge.
Swapping to 12mm hex all around and the +3mm offset Hazard wheels made it drive sweeet. Like a stadium truck almost. Really the single best thing I've done.
It's a no brainer. I will NEVER go back to running the truck narrow. You can drive it so hard with the +3 setup.
Also, I've done a TON of searching about running Avid springs.
For one, they're NOT worth $45 for a set really UNLESS you're really looking for that last bit of performance. Work on your driving skills and keep the truck maintained first.
That said, I went from running blue/green AE's and swapped to Yellow/White Avids. They were ok, but def not "right". Swapped to yellow rears and the truck is dialed, even on slick/dusty outdoor track. They work really well.
The only time the Avids really perform noticeably better is if you're running on a rough track or with really big jumps. They do help a small bit to give it that "plush" feel.
Maifield Setup, follow the most recent one posted EXACTLY.
32/30mm F/R ride height
BFast diff rings. Tigthen and back off 1/8 turn
Slipper: Tighten and back off 2.5 turns. 2.25-2.5 turns out with standard FT friction discs.
8.5, 7.5 or 6.5 motor to get the job done. Gear it shorter and run a bit more timing. 83/18 with mild timing will be ok for an 8.5 or 7.5 to start with for *most tracks.
Also, reinforcing the rear body mount does help. However, the JC Carbon fiber piece is super cool, but may be pricey for some. Simple solution: Take a 2nd stock body mount and trim the front "tab" off of it. Then with the mounting posts off, mount/clamp the 2nd unit on top of the one on the truck. Make sure you get it on squarely and put longer screws in the body posts. It adds significant strength, esp. with the epoxy in there. Drill a couple 4-40 sized holes and bolt it together, just inboard of the body posts for extra strength and to ensure it doesn't separate.