The first link is a hex encoded token, 80 chars, 4 bits per char = 320 bits of information. The second shortened link key is likely base 64 encoded, 5 chars, 64 bits per char = 320 bits of information. These should be basically the same from a security perspective. Is there something I'm missing here that you're suggesting?

Edit: This is wrong and should be 30 bits of information not 320 bits for the shortened form. 64 values = 6 bits not 64 bits.