Technology columnist Walt Mossberg takes a hard look at the differences between subscription and download music services this morning.

In an article ('Rent vs. Own') he looks at music services offering subscription packages, which let users listen to, but not own, as much music as they like in exchange for a monthly service charge.

He notes that these services have attracted a "solid audience", but remain "nowhere near as popular as iTunes".

Complex and restrictive

"That may be because the rental model is far more complicated and restrictive than iTunes, and has several big downsides," he writes.

Problems include the need to pay and to keep on paying in order to maintain access to selected music. Miss a month, and the music files "become inert and unplayable", because of the rights management technologies employed.

Though an iTunes user may have to pay £500 for approximately 650 songs, those songs remain their own. A subscription service user may have paid £120 in the same period in order to choose 500 favourite tracks - but the moment they miss a payment, they loose the whole investment. And if the fees rise they must pay the new price, or lose their music.

Limited usage rights

Subscription services also limit the number of computers a user can employ, and limits portable devices for the music to just two. Users cannot make CDs unless they pay extra - and not all songs can be acquired in the first place.

He describes rental services as complex to use, and points to the incompatibility between the main format used by such services (Microsoft Windows Media) and the leading music player on the market, the iPod.

"So rental users are stuck with inferior portable players that don't sell well and thus don't attract the huge number of accessories available for the iPod," he writes.

iTunes/iPod - the better choice

He suggests such services may appeal to people with a deep thirst for music, and that they tend to have better community-focused features than Apple offers.

Despite this, he concludes: "But for most people, it's no contest: Right now iTunes and the iPod are the better choice in digital music."