That Rotrex supercharger is not big..... About the size of an MB alternator?

Can you tell more about the Rotrex?

Is it a compressor housing just like a turbo, with on the other side a gearbox which increases the RPMs of the pulley 3 or 4 times, or something like that?

And what are the downside of the Rotrex (everything has downsides....)
-a bit loss of power at the crank, to drive the Rotrex (just like any other supercharger)?
-maximum pressure or air flow not as much as a turbo maybe? (not that you can use lots of pressure with standard pistons (are they standard oem?)
-how many miles before rebuilt?

And what are the good things of a Rotrex?

And in what other (standard) cars is a Rotrex used? Or is it an aftermarket kinda thing?

For sure its a nice install which isnt as much work as fitting 1 or 2 turbos is suppose.