The wristband holder is pretty shitty and falloffable: it is bulky and I know two people (one being myself) who have lost their bands accidentally. I've rehoused mine on a woven bracelet.
Being a pre-pay band, this chip does an online authorisation for every transaction, making it sometimes a little slower. But for the same reason, they expose authorisations (not just cleared transactions) in their live online statement.
I recently made my first journey on the London Overground using bpay (I've been on their contactless payment trial for 6 months but using a different card) and I got to see an initial authorisation that I hadn't seen before with my previous (post-paid) card:
0908 Enter train system at Wapping stationthen around close of business on day+1, that Auth gets replaced with the actual charge:
0915 bpay sees this authorization:
Auth: TfL Travel Charge,TFL.gov.uk/CP,GB 29/09/2014 9:14:50 Posted On: 29/09/2014 GBP 0.10
0922 Leave train system at Shoreditch High Street
Fin: TFL.GOV.UK/CP,VICTORIA,TFL TRAVEL C 30/09/2014 18:07:58 Posted On: 29/09/2014 GBP 7.20
Interesting that they charge 10p for authorization rather than the minimum single fare. Also note that the description of the transaction changes (to something less readable, IMO) - that seems to happen from other merchants too. Weirdos.