Quality supercharger and turbo kits - recommend?

[Bogracer]

Can any recommend a supplier of such things?

I have an M30 engines E34 535i, nice and original which I have just refreshed and I am looking to add more poke. Supercharging is the easier route apparently.
When would I need to modify the engine?

Comments, advice and pointers would be great fully received.

[toasty]

ESS seem to be the default choice of supercharger for E46s.

CA Automotive may be able to advise.