So lets do some real life examples:

AFL:

GWS vs Port Adelaide
Lay at $12.50
Lay at $1.08

Adelaide vs Melbourne
Lay at $1.10
Lay at $10.50

Brisbane vs Sydney
Lay at $4.50
Lay at $1.25

Carlton vs Collingwood
Lay at $6.00
Lay at $1.19

Essedon vs Bulldogs
Lay at $1.34
Lay at $3.75

That should do for a quick test.