Battery Replacements, Generics or Official?

I am trying to get some guidance on purchasing a new battery for my PB (15 inch, 1.25 Ghz). It's used and so far it's great except the battery has severely reduced capacity. I ran a terminal command to see what I was getting and it reported a total of around 3000 mAh. I read that I should get a reading closer to ~4500 mAh. So I am thinking of buying a new (and ridiculously expensive I might add) replacement battery. I was going to buy straight from Apple, but I thought a quick bit of research to see if there were generic alternatives that offered higher capacities, and found these two:

http://www.powermax.com/cgi-global/generate_css_temp.cgi?p=a-52096

http://eshop.macsales.com/Catalog_Item.cfm?ID=7096&Item=NWTBAP15AL4800Pre-Order

One is from PowerMax, and the other from OWC (I read about OWC on these forums). Both claim additional battery life, which would be great, but also there seems to be the issue of built in circuitry that won't put the PB to sleep when the juice gets depleted. If this is the case, how do you calibrate the battery? Wait till the thing actually turns off completely?

Anyways, if I could get any feedback from those of you have "aftermarket" batteries in your PB, that would be great. This would help me decide which battery to spring for! If the aftermarkets offer and extra 30-60 minutes of juice, that might be worth it! I've been hit or miss in the past with these types of generic batteries, so I'm hesitant to dive in.

Thanks,
Eric

what terminal command did you run to find that?

ioreg -l | grep -i IOBatteryInfo

I went ahead and just bought an Apple replacement battery...I didn't like the fact that the aftermarket batteries had issues with actually shutting down the PB when the battery was too low. Makes me wonder how you would actually do the calibration procedure. The instructions from the OWC battery - while not really difficult - were more complex (installing some third-party app, run 5 power cycles, etc). SO even if one of these generics would buy me a bit more use time, I would be satisfied if the Apple battery can give me 3 hours. Right now, this thing is giving me maybe 1:30? That's definitely not good enough! When I have the new battery (Monday), I will report on it's capacity, just for the sake of comparison (using the command just given above!).