Had one on my +4. Quite happy with the shape, but not much use when rack loaded with luggage... Hence my thought of rear of rack, a little above brake lights but hanging off the back shouldn't get in the way of luggage/straps &c.
Graham (G4FUJ)
Sold L44FOR 4/4 Giallo Fly '11 MINI Countryman Cooper D All4 '90 LR 90 SW