When it comes to MP3 players, it's pretty much Apple's iPod series vs. everyone else. The best-selling iPod, the iPod nano (2GB *est. $150, 4GB *est. $195, 8GB *est. $240), is now enclosed in an aluminum case, eliminating the biggest complaint against the original version: its soft, easily scratched plastic surface. Despite widespread complaints about the lack of an FM tuner and poor navigation on the iPod shuffle, reviews agree iPod players as a family are the MP3 players to beat in every price class. But after easily swatting away the competition for years, the iPod is now being challenged by several other players in the eyes of some reviewers from CNet.com, PC Magazine, DAPreview.net, IT Reviews and Laptop magazine.

There are tons of places to read reviews for MP3 players, but the most exhaustive coverage comes from those that have covered the iPod and the rest of the market since its inception. CNet.com is perhaps the most complete review source we found. PC Magazine also does a great job. DAPreview.net is a little rough around the edges, but is passionate and knowledgeable about everything to do with MP3 players. Consumer Reports' latest effort encompasses 46 players, but while ratings and recommendations are clear and straightforward, discussion of the individual players is lacking.

Video playback is included on the fifth-generation iPod (30GB *est. $240, 80GB *est. $330). The October 2006 iPod refresh included adding a brighter screen for better video. Keep in mind that if you mainly want to watch movies on your portable player, reviews say you're better off with something other than the iPod. Although videos are a nice perk, reviews say its 2.5-inch screen is just too small for extended viewing. The video iPod is first and foremost an excellent high-capacity audio player, and reviews say video should be considered a bonus rather than a primary consideration. If you're just as interested in video as music, see our report on digital media players , which includes models with larger 3-inch to 5-inch screens, better for watching video and movies.

The most popular iPod right now is the iPod nano, a flash player with a very thin profile. The latest nano is just .25-inch thick, and is a bit smaller than the dimensions of a business card. Because flash players (as opposed to hard-drive players) have no moving parts, they are the best choice for the gym.

On its release, the iPod nano quickly shot to the top of the charts in every major review outlet and has stayed there right up to the present moment. Last year's original iPod nano took a lot of flak over its susceptibility to scratches. Not only is the current model more scratch resistant, but the iPod nano is available in colors: black (80GB version only), silver (30GB version only), hot pink, green and blue.
In the meantime, competition has gotten much stiffer for the iPod nano MP3 player. One example is SanDisk's Sansa line of MP3 players, including the e260 (4GB, *est. $135) , and the Sansa e280 (*est. $270) , which have generally received very favorable reviews. SanDisk players have shot up to be the number two MP3 players in sales -- far behind the iPod but ahead of everyone else. The e-series plays video clips as well as music files. Other formidable nano alternatives include the Creative Zen V (2GB, *est. $80) and V Plus (2GB, *est. $90) along with the iRiver Clix (2GB, *est. $160) . The original iPod's supremacy is also not going unchallenged, with players such as Toshiba's Gigabeat (30GB, *est. $195) and Creative Zen's Vision: M (30GB, *est. $200) getting their share of top reviews.

One consideration with all iPod MP3 players is that you are mainly limited to purchasing music from Apple's iTunes music store -- you will not be able to play music from Window-based online stores like Napster or Rhapsody. That's because iPods are incompatible with music in WMA format that you would buy from most non-Apple music download services. Reviews do say that Apple's iTunes store is excellent, with a wide selection of music, but at this time, iTunes offers no subscription services, and it is possible you will come across tunes not available in the iTunes store. You can also buy music that's in non-protected MP3 format from sites like eMusic.com. For reviews of online music stores, see our companion report on music downloads .

The Microsoft Zune ( est. $230) is a 30GB MP3/video player that goes head-to-head with the iPod. Reviews say the Zune has some great features, including a big 3-inch LCD and local music sharing with other Zune owners via Wi-Fi. Reviews say Microsoft has developed a terrific user interface, which in some cases is even easier to use than the iPod's interface. But the Zune stumbles in a lot of areas. Microsoft has set up the Zune as a closed system, much like iPod. This means that songs purchased from Zune Marketplace will only be playable on the Zune. The Zune Marketplace does offer a $15 per month all-you-can-eat music subscription -- a feature notably missing from the iTunes store -- but otherwise, the Zune is lacking. There are few videos available in the Zune store, and there are only about half as many songs as the iTunes store. Despite the great interface of the unit itself, Microsoft has instituted a corny "points" system for song purchases. Each song costs 79 points, but bizarrely, one "point" actually equals 1.25¢ -- so songs actually cost about 99¢. This strange pricing system gets a "what were they thinking" reaction from all reviewers.