What's the Difference between Cubendi and Shashibo?

I have a bunch of Shashibo cubes, but I haven't yet gotten any Cubendi cubes. I'm looking forward to picking some up.
Can the Cubendi cubes be combined with the Shashibo cubes to make even more interesting shapes?

Intesting I was looking for an explanation so cubendi was not just a knock off I may get some in the future of both brands

Hi can you tell me which is better to buy its a gift

Looks like I need the Cubendi!

Is this ever going to be available in the UK?