the only Noro I've bought (and priced around) is Kureyon.
I love the colors and the effect. when felted it doesn't shrink as much as Cascade 220 or Lamb's Pride, but it gets reeeeeaaaally soft and squishy and snuggly. for me what makes it worthwhile are the colorways (the color combos w/in each colorway).
LYS has it for $8.50
I've seen it at another not-so-L YS for $9.50
littleknits.com charges $6.75
plus tax (I think) and shipping
takes less than a week to arrrive
woolneedlework.com charges $6.59
plus shipping (I don't think they charge tax)
takes about 1 1/2 to 2 weeks to arrive