The manual for my SPIII states it is possible to use Ni-cad rechargeable batteries. What about the Ni-mh type of battery, is it ok to use these? Has anyone tried them?
Yes NiMH will be fine for any application that specifies NiCd.
As an aside, I just bought a Uniross travelmate charger which comes with 2 (plus 2 free at the moment) 2100mAh batteries. It is very light and compact and comes with adapters for US & EU sockets. Works on 115 or 220V and 50 or 60 Hz.
The 2100mAhs are ideal for heavy duty applications such as cameras.
I took it on my hols to Spain and it is excellent. Small enough to go in your hand luggage so that you can recharge your batteries whilst sitting in the departure lounge. Not the quickest charger as it takes a whole 4 hours to fully charge the 2100s.