Mossberg: Consumers perceive Mac desktops as pricey, partly because the company doesn’t play in the very cheapest segment of the PC market, and partly because Apple’s prices include built-in monitors that are often unlisted extras in ads for bargain Windows machines.

But the new iMac actually costs less than comparable Windows machines. For instance, Gateway’s all-in-one Profile 5 model, with a built-in 17-inch flat-panel screen, costs $1,499, compared with $1,299 for the 17-inch iMac, and the Gateway is much thicker and lacks a dedicated graphics card like the iMac’s. Even if you increase the iMac’s memory to match the Gateway’s 512 megabytes, the iMac is still $125 cheaper.

If you tried to match the specs of the base iMac G5 in a traditional Dell tower, you’d also pay more. A Dell Dimension 4600, with the best processor, Windows XP Pro, the best 17-inch flat-panel monitor, a CD recorder and the same graphics card, costs $7 more than the 17-inch iMac. And it’s much bulkier and uglier.

The iMac has some less tangible advantages, too. It has a better, more modern operating system than Windows XP. It comes with a free suite of photo, video and music programs that can’t be matched on Windows. And it frees users from the worry and expense of battling viruses and spyware, because there has never been a successful virus targeting the Mac operating system, and there is little or no spyware for the Mac. The many thousands of viruses and spyware programs that afflict Windows can’t run on, or harm, Macs.

The iMac G5 is another winner from Apple. It’s a computer that’s a real pleasure, not a hassle, to use.