I think I'm going to keep it.

I knocked it down to $465 with reward points, and even with its issues, it looks good at normal viewing distance on my shelf. That's not to say I'm 100% satisfied with it--though I don't remember the last piece I bought from Sideshow where I could say that (and judging from the comments in every thread on this forum, I don't think many other collectors can either). I'm going to contact Sideshow about the stuff I'm not happy about and see how they respond.
I can honestly say that I'm done with Alien and Predator pieces from Sideshow after this though. They're not producing pieces with the quality a buyer should expect for the prices they're charging. I'm desperately hoping Prime produces pieces that really show how badly Sideshow is failing the licenses.