If there were any major issues, would you expect me not to say so?
Here's a full rundown though of all possible minor sonokong g blade differences I know of:
They often use different spelling on stickers, using G Blade instead of BeyBlade, and Dragoon is called Dragon instead. Any japanese text is replaced with korean.
Sometimes their molding is slightly sharper, as in, the edges are more defined, and their plastic is slightly less glossy. That said, sometimes it isn't. Their WD's seem to be made of a slightly different material (like all of their metal parts) and have small, stylized G logos on them (standing for G Blade, their name for G-rev) but weigh no different from regular ones (if not maybe being slightly heavier on average). Some say they are more delicate but personally I'm yet to see any reliable evidence of this, usually it's just 10 wides breaking, which happens with Hasbro and Takara Tomy ones as well.
Every so often, an engine gear may be a little hard to remove from the base or close the base clips on, but I just got a Takara Wolborg with the same problem, so I suspect it was just a small tolerance issue with the base clips or bases during G Rev.
Their colours may vary ever so slightly from Takara/Hasbro, though this is mainly due to the lower glossiness and only really noticeable in one or two releases, Rock Bull probably being the most noticeable, being slightly yellower than the tan of Hasbro's (this could be hasbro changing the colour though, as I lack a takara one to compare to).
Their base clutches are not removable, like Hasbros, the clips to remove the lower half are melted or glued in place. Not a big deal though.
I have encountered nothing else different, and not all of these issues affect all of them, for example I have a Sonokong Dranzer G that is completely like one from any other brand except for the slight color difference of the metal they use (which has a whitish hue by comparison).
All of this has been stated in multiple previous posts though...