My own experience
Hi,
I have owned both. I now have the 13 inch base with the 4gb upgrade. Of note, I bought the refurbished model. Here's a quick comparison **Based on my own experience and usage needs** which highlights why I kept the 13 inch and sent back the 11 ultimate:
11 Inch Ultimate
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Pros:
- Great Pixel Density
- Great Portability
- The "Cool Factor"
- Fast enough to deal with most tasks
Cons:
- Unless you have a monitor, the screen can be a little constraining (this really depends on your own experience/what you're used to...a person can get used to anything)
- Less Volume than the 13
- Less CPU power by .3ghz
13 Inch Base + 4gb
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Pros:
- Better battery (7 hours instead of 5)
- You can fit more on your screen & there's enough room to compare documents (again, this depends on your usage type)
- Better CPU by .3ghz
- Bus speed (I have heard but have not checked on this)
- Slightly bigger trackpad which is easier to click
Cons:
- While portable, it's still a noticeable weight.
- Seems to run slightly hotter/louder
Overall, at the same price refurbished, I preferred the experience on the 13 inch base + 4gb ram over the 11 inch ultimate. This may vary for others as I do not take my notebook with me everywhere. Of note, if I was going to bring my computer with me EVERYWHERE and EVERDAY...I would have probably kept the 11, but to be honest, I don't live on the net and try not to be glued to the computer all the time...it's this years resolution at least.
I hope that helps.