I bought 5 and out of those 3 had a problem. It doesn't complete registration, it doesn't format, very slow.
Stay away.
After requesting a refund from skrutz, I immediately received the money back for the 3 defective ones.

Unbelievably slow. Without exaggeration, at least 5 times slower than another flash drive I have purchased, which had a price difference of only 0.20€. It can take 15-20 minutes or more to transfer 2 Gb. Not worth it.

It broke on the second use and took with it 12GB of files that I had backed up to format my computer. I can't even format it, it's completely useless. It's not even as useless as the ones you get for 5 euros from China, stay away!

WARNING, what you pay is what you get, the product with minimal use for one day tells you it needs formatting and you simply lose your files, STAY AWAY, if you experienced it like me there is a solution but it only allows you to save 2GB per computer, of course don't format, use this program to save whatever you can and then get a good USB like I will do, https://www.easeus.com/data-recovery/data-recovery-software/free-usb-recovery-software.htm

Bought it 3 months ago. Yesterday it crashed displaying the following message: "is not accessible. the disk structure is corrupted or unreadable". Result: lost files of several GB... some irreplaceable. Irreversible damage. The only solution it suggests is to format it to reuse it... I won't buy it, thank you.. It had issues from the beginning, of course.. sometimes it would open, sometimes not, and it was slower than the delay. German company, otherwise good quality... But what do you expect at this price.. The worst USB purchase I have ever made... Stay away...