my opinion as a general whole:

- most oil&gas or other entities are majority held by foreign companies, and because they pay top dollar, they attract talent from all over the place. compare GPA to GPA to see the difference.

- Whether US or UK degree, it all boils down to the ranking or tier of institution you attend, which plays a big part.

- there are more than 500 financial institutions in sg alone. the industry can absorb people all over the place. compared to the number of oil & gas service sectors.

now it all boils down to what kind of engineering you want to do, and see if the supply is available. compare market size and see if ROI is sustainable. IMO China is the next place to do engineering.