What should I get? weight v. battery

[nontechy]

I want to get either the 17044DU (4 cell battery, but only 3 pounds)
Or

17023LU (8 cell battery, but 3.5 pounds)

For both, I'm gonna purchase an extra 8 cell battery which I believe coule be inserted at the back of the battery. Does anyone know how much an extra 8 cell battery cost? I even thought of adding an extended life battery at the bottom of the laptop for the extra 3 hrs, but from this forum, it doesn't seem like that's a good idea.

Does 4 cell battery really give you 4 hours? Or, is it more like 2 hours?
(and how about the 8 cell)

Any advice is appreciated. Apologize for my stupid question in advance. I'm a nontechy :)

[dfumento]

Get the/a unit with the 8-cell battery. You'll love the extra battery life when you need it. I am using the X60s with the 8-cell and it is still very, very light and small.

[nontechy]

If I get the 4 cell battery unit, but buy a 8 cell battery, do I actually add it to the laptop? or do I actually replace it completely?
i.e. is it 4 + 8 = 12 hrs?
OR is it just 8 hrs

thanks.

[thibouille27]

You replace it.
But you can cary both batteries of course

[jimmcclarty]

I have two 8-cells I like that I can go all day with my laptop on. I am at 12% now and still show an hour of life left. I don't know if it is orth it though. I rarely need 8+ hours in a streach so the 4-cell would have been a lighter choice... Over all very happy. We just had a storn this weekend where the power was out for several hours I was able to track the storm through the long battery life and the verizon connection. Yesterday my wife and I were looking for a resterant and used the same battery. I am Very happy with my thinkpad.

[thinkpadneophyte]

What settings do you use? I have to have the screen very dim and the cpu speed on "slowest" to get close to seven hours. If I have the screen comfortably bright (which for me is the highest number - 7) - it's more like 4 1/2 hours of battery life. Am I doing something wrong?