I would not, partly because it is putting the vast majority of your investments into one place.
We are hit with mainland chinese property buyers here, too... and their drive for a "safe" investment (property) has pushed a panic button on the housing market, only somewhat tempered by local buyers / owners not purchasing. You, on the other hand, do not have that mitigating factor...
I do think that this is a 5 to 10 year trend that we are about half way through, and the demand for safe property based investments will eventually fall when a different type of investment is available/ popular, or when investing regulations change in China. As soon as that huge population of mainland chinese look elsewhere for investments, prices will stabilize / fall.
I am also leary of the potential for political rules regarding ownership and taxation to change quickly in Hong Kong. So many changes in the country in the past decade, and looking forward.
So, IMO..
The only reason to buy would be that it was definitely cheaper than renting, in the first 5 years of ownership.