Hi, I am looking at buying a Xootr Swift in the UK. Can anyone help with 2 questions I have:

1. I am 6' & 1/2" tall, I am intending to buy the 'Large' model, is that the correct size?
2. Has anyone had any experience of taking a folded Xootr Swift on the London Underground at peak times- was it a problem? Do the guards try to stop you?

Thanks