[TR] OT- Automotive Creeper questions

[aribert]

I am looking to upgrade my creeper.  I need something for use outside of
the garage where the creeper needs to roll over expansion joint gaps /
slab offsets.  Does any one here have experince with the plastic creeper
called "The Bone".  Other suggestions?  I know ther is an off pavement
version of the Bone but I am not willing to give up too much ground
clearance.  I have a custom made creeper for use inside of the garage
that puts my backside about 7/8 inch off of the pavement - I am spoiled
using it but it is hopeless over expansion joints (the underside clears
the concrete by only 1/4 inch).