Looking into getting a R10 but our range have ledge behind the range mat so it would not be possible to place the R10 at the same height as the mat itself.
Its step down of perhaps 5" so the range mat sits lower than where I could place the R10, would this totally ruin the setup?
Enjoy my ASCII-schematics below 
R10
___/__________________
O_______________| <- 5" ledge that elevates position for R10
ball&range mat