[scott00]

If I got ransomwared I would definitely reformat the drive and reinstall the OS. There's no telling what kind of malware garbage they leave behind. Seems like it would make a lot of sense for the criminal to add you to their botnet, even after decrypting your files.

[scraft]

This is a good point I hadn't really considered - for the massive attacks typically there are pretty thorough write ups about exactly what it does, etc. so that maybe reassurances enough.