I'd argue the latter. It's hard to imagine how you could know in advance that a uFAI has a high chance of working, rather than being one of thousands of ambitious AGI projects that simply fail.

(Douglas Lenat comes to you, saying that he's finished a powerful fully general self-modifying AI program called Eurisko, which has done very impressive things in its early trials, so he's about to run it on some real-world problems on a supercomputer with Internet access; and by the way, he'll be alone all tomorrow fiddling with it, would you like to come over...)