If you going to spend that much money, go Premium.....400K is awful (quality is comparable to the free streams given on SopCast). I have premium, but 1.2MB is not as amazing as I thought.
Plus, a lot of people have been running into problems getting the 1.2MB to work (Silverlight issues), so you might want to consider that too.
If you do go with the premium and have problems, I'll post a link to insturctions to get it resolved.
Hope this helps.