We just bought our Strider Plus 3 and love it!! All the features we love have been mentioned above by others but we absolutely love the setup for 2, bub can face us while still having the second seat attached, we love the look of them, how all the accessories are included with it and how 'glidey' it feels.. We ummed and aaahed for a while and were going to wait until closer to bub being born to buy ours as DS doesn't use the pram much now but we also love the Kingfisher and they've discontinued that colour and are bringing the silver back instead so we jumped on the last Kingfisher one Bubs Baby Store had, not sure if they've discontinued the Kingfisher in the 4 as well?? Might help you make your mind up though haha! I don't know anything about the Agile sorry but love our Strider Plus do far in the week we've had it!