Only use the capacitors sold by HW. I am sure there are plenty of people who will disagree, but until you have experienced the lower motor performance you get from using any alternative to the HW stuff, you'll believe anything!
I've never experienced any problems with the speedo, but I do know people who have, by using the 'wrong' capacitor. People go to extraordinary lengths to pay extra £££s for the best motor and cells, and then want to scrimp on a few coppers for a capacitor! Use the original equipment is my advice, it has restored the edge to my motors. HTH
