As you can see with the first dynamo light I had there is a button and a switch on there so you can turn the "standlight" mode off and a polarity switch I'm assuming so if you put the wires in the wrong way round you just flip the switch without having to take the wires out again.
|B&M Toplight LineTec Brake Plus Rear Dynamo Light|
Only reason why I tried to stick with the original design was that others in the London Brompton Club have had LineTec design for a long time and not have any problems at all.
Now I have the below dynamo light and from what we can tell its ALOT simpler design so I assume alot less things to go wrong.
Busch & Muller Toplight View Brake Plus Rear Dynamo Light
I've had this light on for awhile now and been on some cobble roads for testing and its holding up no problems.
The new light seems to be of a much simpler design and component wise. It has no buttons or switches to play about with.
|LineTec (above) & View (below &on)|
|View looks thinner than LineTec|