I would not call the JRSC a POS by any means.
For those who detest lag in any amount, a postive displacement "blower" makes a hell of a lot of sense. [I'm actually looking at one for my DC4. h:]

That said, a turbocharger is a more efficient form of forced induction...i.e, at a given boost pressure, the intake charge temperature will be lower with a turbo than with a JRSC.

That said, there are some interesting options for intercooling the JRSC. Mike (MrFatBooty) posted a link to a company that retrofits the JRSC intake manifolds with air-to-water intercoolers. PM him for the link if you're interested.

It's a matter of personal preference and budget. Since you've expressed concern about lag, I'd bet you'd be happier with a JRSC. It wil amplify torque much lower than most turbo kits.

If it's at all possible, get some seat time behind the wheel of a turboed GSR and supercharged GSR. Then make your decision as to which powerband feels best for you.