Device integration and performance
These services are made specifically for taking music to go on your MP3 player, so seamless integration and a smooth transferring experience are important.

Rhapsody To Go and Napster To Go both seamlessly integrate compatible devices into their interfaces along the left-hand column. Napster requires that you set up a relationship with each device, a simple process, considering three is the limit.
 
Rhapsody and Napster provide handy boxes within their windows where you can drag and drop desired tracks, albums, artists, and playlists. Within Napster, synchronization is automatic and immediate when you use this method. Napster To Go lets you continually add more songs during syncing, which we found handy since it's easy and quite fun to pick from their 3-million-plus song catalog. Unlike Napster, Rhapsody does not allow you to set up an automatic syncing relationship for on-the-go content--a bummer; it will automatically synchronize dynamic playlists, but not standard library contents.

The most confusing issue that you'll run into with syncing your player is figuring out when you need to connect to ensure that your content does not time out, say, in the middle of your vacation. Rhapsody makes it easy, as it simply requires you to sync once per month; after that, you're good for 30 days, regardless of your billing date. The other two services require you to sync soon after your billing date. With Napster To Go, you must sync at least once a month, within 7 days of your subscription payment date. So if your billing date is June 1, your content will stay fresh until July 8, meaning you're safe to go away for Fourth of July weekend. However, if you have a longer vacation that begins before your billing date and ends after the grace period runs out, you'll be out of luck unless, of course, you tote your computer with you. With both services, the rules remain the same even if you pay for an entire year up front: you still have to sync monthly. We were informed that this is inherent to Janus--the technology won't allow licenses to stay fresh for a whole year. However, this isn't really an issue since you'll probably want to refresh your content often, given the huge selection.

We timed subscription content syncing for both Rhapsody and Napster using a Creative Zen V Plus and got nearly identical results. On average, music transfers at a rate of 0.35MB per second. This definitely isn't speedy, so if you're syncing massive amounts of content, it's something to keep in mind.

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