Does anyone have any experience of the above plant?

I am trying to find out it's final height.

The label says 75cm (30 in), in which case I have the perfect place.
Whilst looking up on the internet I found a website which said it would grow 90cm x 90cm max.

Looking further I have now found references to it's overall size being 1.5m x 1.5m, in which case I have another perfect spot for it!

So the question is can anyone suggest to me what its final size could be (I live in the Highlands, Scotland- but our 'micro climate' is actually quite pleasant, not too cold or wet) so I know which of my two spots would be best to plant it in.

Thankyou.