So that leaves the issue of donationware.
Just to be clear - from this site you can use the apps for free indefinitely.
A donation avoids a 'gentle' nag. That implies that the app is not stealth. But then, lots of PFC apps are not stealth.
What is the general view on donationware? Is it tolerable? or a No-No?
I think this qualifies as "Nagware" because if you have to pay money to get full use of the program without annoyances, it's not freeware. One exception is FileZilla and Transmission (two of my favorite file transfer clients): these nag you every few times you start the program, but provide the option "don't ask again".
Site policy is (as far as I know) anti-nagware based on the entries for Disk Digger and SilentNight Micro CD Burner.
Personally, if its a program you use once in a great while and does something really fantastic, I'd be willing to use nagware. If its daily use, I'd start looking for something else. I used to love WinZip but the nag screen drove me crazy.