I've only seen 2 other Oysters in this area. I said Hi to the lady pushing the first and said "Oh, I've not seen another OPyster user before" she looked at me like I was a freak 
Do you know what the guidelines are for the pushchair bit? Louie is sitting straight and holding his head really well, but isn't able to do this unaided yet. I think once he can he should be alright to go in. He's filling up the carrycot both width & lengthways!
Since Louie has been in his cot, we're having to do a few extra dummy runs but overall his sleep isn't too bad.