I had read from reviews of some different crochet hook sets available on Amazon that the sizing was bad, but there didn't seem to be any mention of that problem with this set so I went ahead and brought them. Firstly, the awful carry case they came in broke the first time I opened it. This wasn't a particular problem as I already have a case but people who are buying these because of the carry case may be disappointed!
Now on to the hooks...when I checked them all in my needle gauge, the hook marked as 8mm was actually 7mm, the hooks marked as 7mm and 6.5mm, were both 6mm (meaning I had three of the same size as they had managed to get the 6mm hook correct!), and the 4.5mm hook was 4mm. The rest were ok-ish, only slightly above or below the size by a small amount but still, I was a bit miffed. I still considered keeping them but when I tried to use one, a slight ridge on the inside of the hook kept catching on the wool. For a set that is marked as 'high quality' I don't really want to have to sand all the sharp edges down! Yep, so all in all disappointed, will be sending them back.
Bit of a shame really, they were nice bright, lightweight, colourful hooks that I would have liked to have used!