the 4 speed Sturmey is ok... providing you have an indicator rod.. they are different from the 3 speed ones [ totally ] the levers are ok as long as the spring that keeps the lever engaged in 1st gear [ it needs a lot of tension ] is in good order. The last one I was using was a bit weak and wouldn't stay in 1st which can be terribly annoying on a 1 in 5 hill

......
it was so bad that it would jump out of 1st into 3rd

amusing but would be a danger to the nether regions on a bike with a cross bar, the Moulton is ok in that respect...
