I've got one! I use mine for my minature shetland (31 inches) and it fits almost perfect so i would have said for anything bigger than a shetland you would need the pony one! They give lots of measurements in the catalogue so have a measure up against the pony! I think the shafts on the pony one have some adjustment but on the shetland one they are fixed, so dont forget to take his into account when you measure!
what a georgeous little mini! thanks for your help. i measured little girl last year and can't remember outcome, she won't let me catch her at the mo so i guess when she decides to come in for some food i'll get a chance to measure her again! looks like i'll need to go for the pony size by your pictures! 10.2 may be ok but i think 11.2 would be a bit big for it.