Stillen intercooled supercharger Stage 3 will make a claimed 407 bhp without other mods. You can add induction, exhaust, headers to that....
As noted previously, superchargers are less cruel to the engine (less heat, progressive power delivery) and produce power in a way better suited to the big, flat torque curve of the original VQ35 engine making it drive like an NA car with more power everywhere. Turbos tend to produce their power higher up the rpm range and, as noted, can have quite violent power spikes.
Both turbo and supercharger are limited on boost potential due to VQ35 engine internals being a little suspect at higher levels. All the parts are available to beef it up, but cost wise that's a whole new ball game.
Stillen intercooler is air to water heat exchange inside the manifold with only a small (ish) chargecooler out front, so the interference with radiator airflow is minimal. If you want more engine cooling capacity, a Koyo aluminium large capacity radiator is available.
The APS turbo kit was originally designed for the USA LHD market, although a RHD kit is currently under development.
Obviously turbos have their supporters as do superchargers, but more S/C kits have been developed for the VQ35 than turbo - must say something, even HKS have a S/C kit now!