Adding pressure to an engine is a very effective way to add power. The draw back to this is the cost of new components and a timing retard device. While some people will just point to a local junk yard and say grab that turbo for $75 and add a MSD retarding box, not all of use are OK with a used part. No matter how many times YOU have done it.
The added expense of plumbing a turbo and if the pressure is high enough, a intercooler becomes a bit complicated for some and a pain to puzzle piece the piping in.
A bolt on super charger is pricey but easy. And many will pay for the ease of installation.
All of those that want to quibble over each parts bennifit can find the thread on it and re-start it back up.