My eldest still rode in a Phil and Teds double until she was over 4. The only reason I got rid of it was she was too tall, and her feet would press down on the front wheel, making it impossible to steer properly!! I wish I still had it for walks and jogging though!

I second MadB's suggestion - invest in a very good baby carrier - a Caboo for when you have the newborn, and a wrap or Mei Tei later on. You will have the best of both worlds, and still get by with a single pram. Plus it means you can wear bubs at the supermarket and have the elder in a real trolley Trust me, not having to stack your shopping all over a pram is fabulous! LOL