The MM-5600's excellence shows when you first flip it open and see its 240-by-320 screen, which is an extremely high resolution for a phone that isn't a smartphone. (Smartphones are high-end phones with a built-in OS, such as Symbian or Microsoft Windows.) The screen is simply breathtaking: bright, razor-sharp, and utterly beautiful. It even makes reading text on WAP pages almost fun.

Like other Sanyo phones, the MM-5600 has an extremely loud and strong earpiece and speaker. Voice-transmission quality was unusually good, and signal reception was excellent. Voices sounded a little muddy until we moved the phone down on our ears a bit, which fixed the problem. With analog roaming capability, you're not limited to Sprint's all-digital network, either.

Want more features? VoiceSignal speaker-independent voice recognition combines with a top-notch speakerphone for an excellent hands-free experience. High-quality ringtones (in the AAC music format) sound clear, picture caller ID looks good, and the MM-5600 is Sprint's first phone to support video ringtones (though we're not sure what their use is, because you can only see the videos when the phone is flipped open.)

The MM-5600 has unusually good multimedia and PC-connectivity features. The phone takes Mini-SD memory cards and, when you plug it into a PC, the card appears as a hard drive on a Windows XP desktop. No muss, no fuss, no software installation. Uploading and downloading pictures, videos, and MP3/AAC music files is the easiest we've ever seen on a phone, though you can't upload ringtones from your PC to the phone or sync your address book without third-party software.

Speaking of pictures, the camera is moderately sharp with well-balanced colors, but suffers from distracting compression artifacts. (Check out our camera phone gallery and see for yourself.) Videos look extremely compressed.

The phone's built-in music player supports unprotected MP3s and AACs and has a shuffle mode, but no playlist support. Music sounded great through our wired headset. You can also watch Sprint's streamed MobiTV channels. Those come through smoothly, but appear extremely compressed. (The culprit here isn't the phone but Sprint's relatively slow network.) The MM-5600 can definitely handle high-quality multimedia and games: It did well on the JBenchmark Java benchmark tests, especially considering its high-res screen.

Unfortunately, Sprint bars real IM and e-mail clients from its phones that aren't smartphones, forcing subscribers to go through a WAP portal. That's not Sanyo's problem, however. Once again, it's a Sprint issue. The phone could also be a little smaller, picture quality could be a little better, and we'd love to see Bluetooth here. But these are mere quibbles. If you have the cash, the MM-5600 will make the most of your Sprint subscription.

Benchmark tests: JBenchmark 1: 2272 JBenchmark 2: 109 Continuous talk time: 4 hours 9 minutes Benchmark test results: Jbenchmark 1: 2272 Jbenchmark 2: 109 Continuous talk time: 4 hours 9 minutes

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