I never saw much of Jimmer in college (not a college basketball fan). In fact, I only saw one half of a game -- his last. I wasn't much impressed and didn't think he'd be more than a JJ Redick, despite everyone getting angry of that comparison came up. Despite this, I felt getting him with #12 last year would have worked on numerous levels, assuming we'd run the ball through Hayward more and rely on a PG to have some ability to start the offense and to mostly spread the floor away from the ball. I also didn't think it'd be great, with how young our team was at the time, to be looking for a PG that was young, and since Jimmer spent 4 years in college I viewed it as a plus. Alas, he was never available at #12 so it didn't matter.
A lot of my attitude on Jimmer really changed when I saw how annoying it was that the entire arena erupted every time Jimmer touched the ball. This was almost unpardonable. Simply disgusting and I'd had for that to continue forever. I'm a Jazzfan above anything else and having thousands of Jimmer-version Sloanfelds would be unbearable.
This being said, if you can pick up Jimmer at a low price (depending on what they're asking), then you do it. It's a minimal risk. The only risk is the annoyance factor and the possibility of distration.
However, I see Jimmer's ceiling as a slightly lower-profile Mo Williams, which can be a good thing depending on how you run your team. Obviously, however, we just acquired Mo Williams.