Both run Windows XP Home Edition, and both carry 1GB of RAM, a webcam and mic, and in essence everything else, except the MSI Wind U123 features a bulbous nine-cell battery and the 1.6GHz Intel Atom N280 processor (versus the U100's N270 CPU). In short, same stuff, different day.
That CPU upgrade doesn't amount to much of a difference. Oh, sure, the MSI Wind U123 will finish tasks a hair faster, but it's still in the same ballpark.
While the U100 earned a mark of 36 in WorldBench 6 (about the average), the MSI Wind U123 barely edged ahead with a score of 37. As for the U123's large nine-cell battery, however, our Test Centre found that it lasted for 4 hours, 34 minutes under constant use, whereas the three-cell battery on the U100 survived for a little over 2 hours less - that's an obvious improvement over last year's model.
(Of course, netbooks with longer battery life and more features, like the Toshiba NB205-310, are on the market too.) The only drawback to the MSI Wind U123's beefy battery is that it makes this netbook weigh as much as an ultraportable laptop - 1.63kg, to be precise.
The MSI Wind U123's 10.2in LED screen is crisp, and a tad larger than the 10in screen found on the U100. Although the workspace is a little tight, Excel spreadsheets seem clear and web browsing is easy enough to handle. The matte screen allows for fairly crisp colours indoors; though the antiglare surface is nothing special, it does its job well away from direct sunlight. Once outside, however, the 1024-by-600-resolution display appears dull and mediocre. At least it's viewable - most netbook makers prefer to go with a glossy screen that's barely visible outdoors.
The MSI Wind U123's touchpad is extremely responsive, allowing your finger to slide effortlessly across its surface. The one downfall is that the mouse buttons are resistant, a little too stiff and clicky for our tastes. Translation: it's a less-than-ideal choice for use in quiet places such as a library or classroom.
The MSI Wind U123 keyboard is 92 percent of standard size. Of course, while that is common to netbooks, it doesn't take away from the fact that such keyboards are still a little tough to use. Case in point: after an hour of almost constant typing, small hands started to cramp up and we had to stop.
If you put the MSI Wind U123 side by side with a netbook such as the HP Mini 5101, you can see that the U123's keys are just a hair shorter.
Layoutwise, the MSI Wind U123 doesn't veer too far from what you'd expect. The U123 has three USB ports, two on the left side of the unit and one on the right. You'll also find a video port and an audio port for headphones and a microphone, plus a multiformat reader that supports four different types of memory cards (SD, MultiMediaCard, Memory Stick, and Memory Stick Pro).
The 1.3-megapixel webcam is slightly better quality next to the webcams on other netbooks in this category; it records video well and captures footage with only a few minor colour and sharpness issues.
The only unadvertised feature of the MSI Wind U123 (and one that matters to 0.05 percent of the public) is the machine's openness to hacking. The U100 is a good "hackintosh" box, one that allows users to download drivers in preparation for installing and using OS X on a netbook. Hackers, now you have a newer version to consider ripping apart.
NEXT: our expert verdict >>