It is often difficult to keep 24/7 live programming when you are just getting started with your station. Having archives is a great way to introduce people to your station without requiring them to tune in at the exact times that live broadcasts are happening.
Unlike SoundCloud, Mixcloud has arrangements with publishers to to pay out royalties to artists that appear in the mixes you upload. In addition there is no time limit restrictions, you can upload as much as you want. Many radio stations are taking advantage of this and hosting all of their archives over at Mixcloud. One thing that Mixcloud lacks is the ability to make your podcast downloadable.
Good ol’ XML podcasts are still in widespread use. Many people still subscribe to podcasts on iTunes. Its a bit complicated to get an XML file generated by hand, there are many services that can generate one for you (including Streampusher).
SoundCloud is quite strict about copyright, so if you are uploading a mix with popular copyrighted music it is likely to be taken down quickly.
However if you are using royalty free music or music you own the rights to, this is of course no problem. Talk radio or podcasts can also be well suited to SoundCloud.
Want to automatically export all your archives to Mixcloud, an XML podcast, or all three? This feature is now on Streampusher. After you upload your tracks to streampusher, you can export them to your favorite services in just one click.