The one in Bristol went bust several years back. Hardly surprising. They only had about 3 stands in the city itself (and 2 out at UWE Frenchay / Fishponds).
The city stands were all in the centre of the city, so you could not bike out to anywhere as there was nowhere to return the bike to. You could not bike into the city as there were no bikes available in the suburbs. To top it off, all the in city ones were only about 10 mins walk apart, so it was actually faster to walk then to get a bike, cycle through city centre heavy traffic and park the thing again.
UWE was still promoting it after the bike stand on one campus was empty for weeks and the 2 damaged bikes on the other looked unsafe to ride (rusty chain and brake cables).
The parent company right from the very start seemed to make no serious effort to look after the bikes or site them anywhere genuinely useful. I wondered at the time if it was some kind of tax write off scheme or similar and was never intended to actually work.
I think you can now rent Bromptons down by the Temple Meads train station which seems rather fun – they have some kind of locker system there – its a different company to the one mentioned above I think, seems more sorted. I presume you have to return the bikes to the same place.