I think that I am qualified to answer this, I spent hours researching batteries for longevity versus price and availability. If you want to use Alkaline I found in order of performance:
Alkaline
1/ Hi Watts, these have a green housing are available from Electrocomp as well as many other outlets, I found up to 20 % better than Duracell/ Energizer. Never seen performance like this in a Alkaline chemistry. The units I tested were consistently 1,6 volts with a load.
2/ Energizer Alkalines
3/ Duracell
Li Ions
Its a close run thing between
Energizer Blues and "Power Plus" from Electrocomp. These have now been withdrawn from sale due to a clash of Ever Ready trade marks...so its Energizer blues and they are also half the weight of Alkaline. I think they are importing another Li Ion brand now though. Give them a call.
http://www.electrocomp.co.za/
Plus they are cheaper...these are primary batteries remember and cannot be recharged, this is why the units that came with the device lasted so well...
Paul
Centrifugal force in pure Physics does not exist, however this does not apply to Taxi drivers..