Depends.
I am from France and I have noticed that Management is more valued in France than in other countries - here if you did something like MSc Management at HEC Paris (top business school) then employers literally reach out to you. Management associated with top French / American business schools like HEC, INSEAD, Wharton, HBS, Stanford, ESCP is definitely prestigious.
In the UK, Economics has more charm, especially from places like UCL / LSE. With econometrics, it is associated as more quantitative.
You've mentioned Warwick - its business school is also one of the best in Europe. Warwick Business School is in fact much more famous in France than Warwick University itself, so Management there is a good idea.
Also, Management is good when it provides you with the opportunity to take MIS modules - management information systems / tech management etc.
I guess if you're more into quant / econometrics stuff choose pure economics, if you're into managerial stuff choose the latter. Ultimately, I don't think it will make much difference. A greater difference will be, for example, whether you go to UCL or Bristol to be honest.