Also, centrifugals need to be tapped into the engine's oil system to provide lubrication for the s/c. Roots and twin-screws don't. Whichever s/c is chosen, the fuel system needs to be upgraded and re-tuning is a must.
Almost every centri manufacturer has now migrated to a self contained oiling design - even the smaller manufacturers. Tapping the pans is no longer an issue. Vortec, Procharger, and paxton all migrated years ago.
The procharger is extremely loud at idle. Sounds like busted bearings inside and that's something that takes getting used to.. They also have an extremely loud blow off valve and whistle notice-ably at cruising spead.
Paxton and Vortec have a much quiter idle, still have a cruising whistle, but their kit blow off is quieter.
Here's a video of my procharged mustang, you can hear pretty much everything I've mentioned in this one clip..