7. Open an e-mail and click on a link to watch a movie preview, adjusting the display as necessary.
This task tested display quality; here, the MacBook Air edged out the Portege R500 and the ThinkPad X300. Thornton said that's because testers believed the Air had a brighter display. The Lenovo's display quality lagged behind the Toshiba's on this test, according to the testers.
8. Connect the computer to a projector and project the laptop display to a screen.
The Toshiba Portege R500 was the winner in this test, with both the fastest completion times and greatest ease of use. Users particularly liked that it and the Air started projecting images immediately after the projector was plugged in.
By contrast, testers found the correct plug-in port on the Lenovo ThinkPad X300 more quickly than on the other two laptops but because the Lenovo didn't automatically start the display after the plug was inserted, users lost time finding the correct key combination to start the projection. "Almost everybody failed or had errors doing this task on the Lenovo," Swinkels said.
9. Shut down the computer.
The MacBook Air was the clear winner in this seemingly simple test. Shutting down the Mac required about 10 seconds, on average, which was four times faster than both the Lenovo and Toshiba. One common error on the Windows-based laptops was that testers pressed the power button, which puts the computer to sleep but doesn't turn it off. They then had to start again and figure out how to fully turn off the laptop.
The envelope, please
In the end, the testers found the Apple MacBook Air to be overall the most usable of the three ultrathin laptops, although it didn't excel in all the tests and categories. The Lenovo ThinkPad X300 was deemed the second most usable laptop and the Toshiba Portege R500 came in third.
"The MacBook Air has the clear edge over both the Lenovo and the Toshiba in terms of usability metrics," said Thornton.
The overall results were extrapolated from three factors. The first was the time it took for the testers to execute each of the nine tasks. "On average, where there were reliable differences in time, participants completed those tasks about a full minute faster using the Mac Air," Thornton said.
The second factor was the completion rate for each task for each laptop. Most users completed most tasks, but sometimes there was a difficulty and the task was not completed.
The third factor was the subjective comments of the testers.
Although the MacBook Air came out on top overall, the results varied from test to test, according to Thornton. For instance, the Air only had a slight advantage over the Toshiba Portege R500 when it came to testers' subjective opinions of portability, although the Air had a wider advantage over the Lenovo ThinkPad X300. And it was a dead heat between the MacBook Air and the Lenovo in terms of which had the most functions and features, with the Toshiba lagging behind.
The Lenovo was highly rated for its durability while testers felt the MacBook Air was fragile, Thornton reported. The Toshiba was considered by testers to be the most portable and compact, and it was virtually a dead heat in terms of which of the three laptops was best for business use in the testers' estimation.
The Air was, by far, considered the most fun. And testers made the MacBook Air the clear winner when asked which laptop they'd purchase. Testers also considered the Air to be the best value, according to Thornton.
So although the other laptops also had their strengths, the bottom line is a clear win in usability and user perception for the MacBook Air.