DS2 is due in 6 weeks so planning to get a P&T Sport. Happy to buy new especially as just got a bonus but friend of a friend has one she is selling for £150 so wondering whether I should make do with that. Is in fairly good condition though missing the instructions. Think it's a couple of years old. Does anyone know if the model has changed a lot in the last few years which would make it worthwhile getting a new one?