deleting after installing wpsmuchpro

I've replaced with wpsmushpro, and it looks like i'm being promted to compress using the pro. are the compressed files still there. It shows no files being compressed in the pro setup.

If I delete the files, what exactly am I deleting? Are the compressed versions in addition to the original non-compressed?

Or by deleting am I deleting all my previously uploaded images (completely) that have already been compressed by