AVCHD/Pro Res/ What's going on?

Question

Hello Everyone,
I want to take things a little farther in my understanding and use of FCPX (10.1), to know exactly what is happening with importing, mixed files, etc. Generally I use 30P, highest quality.
So, I'm using several cameras to video events, Canon HF G20, HF M41, HF R42, and an HV20(old firewire unit). The HF G20 is basically the master. Others are focused on particular things. The G20 and M41 will be set at 30P, the R42 at 60P. I want to know the best way to handle the importing of these files into FCPX.
When I import, I start with the G20 via USB using Create Optimised Media. I believe this results in:
          An EVENT File (let's say EVENT X) that is Pro Res 30P.
Importing from the M41 is the same using USB, using Create Optimised Media, so I believe that:
          It is ADDED to the EVENT X FIle at Pro Res 30P.
Then I add the HV20 to the same EVENT X File via firewire, using Create Optimised Media, and I believe that:
          It is ADDED to the EVENT X file  BUT, since the HV20 is different the video will be transoded to fit with the 30P EVENT X.
Then I want to add the HF R42 files to the same EVENT X, BUT, since it was recorded at 60P, what will happen.
Also, I plan to use some video taken from iPhones and iPads.
So basically, Is my understanding correct in all this, that the files are altered to fit 30P?
Also, Is there any benefit to using something like Clipwrap or some other converter softwarewhich claims they don't change the actual video file but change it in a completely lossless manner? Or is there a better way of importing?
Thanks people.

Answer 1

Tom and Ian, thanks for the responses. So with events, everything is imported "As is", just converted to Pro Res files. Then, when I begin a project, the project takes on the settings of the first file that is imported, correct? So when I import files that are different, what will happen. FCP will just deal with it, not alter the files, just take the differences and go with them, or?
Thanks again.