Why not, N900 on regular BL-5J does have ~7 days of *real* standby time (i.e. radios disabled, not touching device, etc). Maybe even longer, I couldn't be bothered to test it longer, as it's pure numerology.

No problem It is the middle one, yep? Funny fact - I own exactly same battery myself, was inside one of N900's I've bought. I tested it for sheer fun, using external RC charger, and it was ~1200 mAh (it was used, so original capacity could be 1300 mAh, indeed).

Anyway, your friend must have been hit by placebo effects, as label capacity is fake for 99999999% percent. By pure physic, you can't put more than ~1400 mAh in BL-5J form factor. If you abuse form a little, and make battery thicker (like Scud or Polarcell did), it get ~1500 mAh Q10 max (i.e. during constant current discharge of 1/10 total capacity - you'r relative capacity during real-life usage may be higher, like 1600 or 1700 mAh, even).

That's all about it when it comes to Li-Ion - until some completely new technology arrive (like nanowires or whatsnot), you may be absolutely sure, that everything claiming higher capacity is fake. and believe me, when something new arrive, it will cost 10x or 20x more than LiIon cells, at start

Also, when someone claims, for example 1600 mAh (like Maxxim), you may easily verify it by checking cell thickness - if it's not "fatter" than Nokia's BL-5J, you may be sure, that advertised capacity is fake, too.

Frankly, we have been through that topic dozens of times - but don't worry, I can't really blame you for not reading 157 pages of this thread

/Estel