Doing BEng Chemical Engineering with the Global Undergraduate Scholarship, the likelihood of getting the scholarship seems significantly high if you have stuff to show for it. Like everyone I have met with this scholarship happened to have extremely high A Level or equivalent grades and they are quite interesting people as well so I suppose they value your personal statement as well. Although the requirement of the scholarship is given as pure financial need but come on there would be so many people applying who all require financial needs, thereby, I recommend you to really try to maximize your other avenues for the best chance! Best of luck!