Is this a good supercharger?

I haven't heard bad things about Paxton.... don't really know much about them except that they exist haha. That's significantly cheaper than the Roush, Saleen or the FR (Kenne Bell?) by about 2k. Everything I've heard though is Saleen or Kenne Bell is the way to go because the Roushcharger is a less efficient design. I don't know the specifics.

Depends on what you want. The centri type superchargers (Paxton, Procharger, Vortech) are great for high rpm, but you won't notice much below 3000 rpm. Their boost is a function of rpm. The positive displacement superchargers like KB, Whipple, Roush, Saleen, Magnacharger, have full boost throughout the rpm range--as low as 2000 rpm.

At the track, the centri's are just as fast (or faster) because you don't need the low rpm range that they are lacking. You're motor will probably live longer too, since you won't be driving around under boost as much.

For fun around town, I'd rather have the roots or twin screw, but you pay more for it. I plan on trying to find a good deal on one of these. Twin screws are technically more efficient, but for me it doesn't matter that much. Price matters more, so I'll include a magnacharger in the selection. These types are harder on your engine too, because of the low rpm power/torque.

That tuner kit that you linked to doesn't include everything you need. You'll still need injectors, fuel pump, tuning, etc. Count on a minimum of 4k for a complete, cheap centri kit, and 5k for a cheap twin screw/roots--non intercooled, add $1000 for intercooler or $400 for water/methanol injection.

and if you look at the bottom of the page it says it doesnt.better call.

Whatever you buy make sure it's intercooled. An intercooled centrifugal system complete with all that's needed will run around 5k no matter what brand you buy.

to the NOVI 1200 standard system will require ECM programming and could require additional parts, consult your Paxton representative. Tuner kits do not include the fuel pump, fuel injectors, MAF housing, DiabloSport MAF.ia. and DiabloSport Predator.