I have bought one of these from Exmoor Trim and will fit this in a matter of weeks... I will let you know how it works.
The only thing that still worries me is that the 'net' (it looks like some sort of net) below the seat which holds it in place when someone sits on the seat is torn apart... This means that the seat is sagging down, does anyone have an 'easy' fix for this or can you buy this as a sparepart?