I have a baby jogger zip as my second buggy for about a month now and I love it! It's nippy about town, easy least to get on the bus and can handle the towpath with no trouble at all.
Anyway, just thought I would share that I have discovered that the IKEA trolley bag m.ikea.com/gb/en/catalog/products/art/90149148/, sold for a princely sum of £2.50 can be used as a travel bag for the zip, and it even has backpack straps!