DVD wasn't even copy protected...

Enker, if you have the time, check over the linked guide to make sure it was done right.

I've also updated the DVD DIC guide with a link to the above guide.

Here are additional steps for protected discs:
QPxTool
1) Run readdvd.exe -d D: -o NUL
2) Press Q to stop reading and then copy the three keys from the command window (decrypting disc key, trying player key, decrypted disc key).
Protected disc template:

Region: #,#,etc. (list all)
RCE Protection: No or Yes
Copyright Protection System Type: CSS/CPPM
Encrypted Disc Key: 
Player Key: 
Decrypted Disc Key: 

Did you play it for a few seconds using VLC before dump?

Nope, I didn't. Should I? Nothing about it in the wiki.

In the meantime ImgBurn did the job, dump matches the db.

any good advices for dumping them?

DIC doesn't seem to work for me, either with a 712A nor 2 different 716A using the command

DiscImageCreator.exe dvd f: gowii_bonus.iso 8 /c

TIA