Oh - forgot to say I've also got a Fenix TA30 - awesome bit of kit but a bit bigger that the others - it's now my main camping torch at 3.5hrs run time @ 225lumens is awesome

The 60 lumen setting is adequate for almost anything though and that's 25 hrs. It runs for 115hrs @ 9 lumens! To give you an idea of how bright 9 lumens is - you can stand it on it's tail and shine it to the ceiling and it lights the whole room up - easliy bright enought to eat under etc.
As for batteries, well, I use different batteries for different things.
For the RC-N3's I use Eneloop NIMH rechargeables as they are my main bike lights - I have another set always in my pockets if I end up riding for a long time so I switch them mid ride. I also have a stock of Panasonic CR123's (the best apart from Sanyos - steer clear of Energizers) if I want to use the toches in one cell mode (i.e. smaller). rechargeable CR123's (i.e. RCR123) aren't worth bothering with imo.
For the Fenix TA30 I generally have a pair of AW 17500's charged up and ready to go. Burn time and output is reduced by about 20% but it works out very economical using those - quite expensive initial outlay though - about £7 for each cell and £14 for the charger.
The TA30 can also use 3 CR123 cells - which is when it get's it's max run time intensity. If I'm going for a long walk or extended camping trip I'll use those instead of the rechargeables.
As for where to buy them - everything comes from the US or Hong Kong -much cheaper than buying them from the UK. Panasonic cells are working out at about £9 delivered atm from various ebay sellers - you have to keep checking though as they aren't always listed all the time.