I rarely purchase refills. Its either due to stubbornness or pride, but I often feel that with a little creativity and time, I can come up with my own sounds, rather than surf through someone else's presets. Sure, you can learn a few things by studying a patch that someone else has put together, but with only a few exceptions, I tend to shy away from commercial refills.
However, having said that, the price for New Atlantis Audio's Polar Elements refill makes it hard to beat. At just $5 there are some nice sounds to be found in its 50 combinators. I especially liked Cold Sunrise, Dall's Horn, Dense Descent, Gakkel's Secret, Inupiaq Bells, Sagging Moraine, and Uria Flutter. The combinators for Orca Straight and Welcome To The Top are just beautiful.
Check it out if you're looking for something cheap and fun.