Go with the Greddy SC! My friend got his installed a couple days ago and it took 3 hours by a friend who used to install SC for Ford trucks. The kit is a true bolt on and is more reliable and cheaper than a turbo.
I've got a turbo system on mine and from other forums I've read, supercharged is less troublesome than turbocharging for the xb. To "fix" my system of some of the problems it is having guess what? I have to spend more money to get a fuel management system that will really work as opposed to the apexi safc2 that I currently have...but I'm probably looking at spending another $1000-1500 (emanage ultimate, return fuel line, fuel regulator, fuel rail, retuning) just to get things fixed once and for all...of course once I do that, I will probably get more hp than a supercharged system.
SC are all internally oiled which makes them better for daily driven cars and there's no lag but it does take power to make power. Turbos need to be dialed in and are more tunable for your style of driving. Research both and find what fits for your application