I have to say its really nice to have all five pieces of the story in my hands now. I am about to start running them, and with regard to Artifacts Unbound, WOW!. I expected a few campaign hooks and plot ideas but I am floored by the sheer number of plot points presented in the pdf.
The range of options presented is really nice as well and I find that Psychic Highway to Hell really harkens back to one of the quirkier old adventures, Harlequin's Back, which was a favorite of my old table.
One of the things I liked most was the mass of NPC statistics, both general and specific. That alone means, that long after the adventures seeds in Artifacts Unbound have been played, Artifacts Unbound will remain in my stack of core shadowrun books.
All in all a very nice product, one that I will very much enjoy.