These look useful, long life with much improved relaibilty and works just like a normal pot. Added bonus is a range of swept angles 35 to 360 continuous so no need for any gearing to maintain resolution. Definite upgrade item if the rest of my rig works out. Tad pricey though £10 to £15 for one offs
http://uk.farnell.com/bi-technologies-tt-electronics/6127v1a90l-5/sensor-hall-0-2v-20v-to-10v-pin/dp/2319673
http://uk.farnell.com/bi-technologies-tt-electronics/6127v1a90l-5/sensor-hall-0-2v-20v-to-10v-pin/dp/2319673