William would be skeptical.

The type of skeptical where he says,

"If you're the one who turned me, then you pretty much ruined the promise of a good life for one where you choose. You're an ass; leave me to my own devices to do what I wish with the curse you have forced upon me."

He is, of course, thankful that he can live ETERNALLY, just the fact that he can't ever see the sun again and that he can no longer remember his passwords to his Robocraft accounts makes it useless; now he can't spend eternity playing games, watching movies on Netflix, and reading books on his Amazon Kindle Fire HD.