for shure, i like the silently r(gl)iding thru the metropolitan rushhour, faster than every car and as fast as my speed with the "red zora" 20 years ago.
the conversion of "mothers little helper was very easy and i fixed it in just 2 hours. my mom (73 y old) is very happy, no more problems with her knees and if she wants more comfort, she drives in the mofa mode (in germany illegal, but she knows and wanted to have). give your wife a bright smile and o lot of fun with just a little money and work.
this is my actual conversion for a good friend. mx 20 directdrive 250 W, 36 V / 14 A controller in front bag, thumb throttle with on/off, pas-sensor, step-down 36 - 6 V, 36 V / 11,6 Ah LiMn, vmax 33 km/h - more pictures > http://commonman.de/wp/?page_id=3777