Disclaimer: I am a St. Gallen (HSG) alumni.
Frankly, if you want to work in Finance in German speaking Europe (and esp. in Switzerland for the great salaries) St. Gallen is a no-brainer.
MBF is most likely even better in this regard than the MBA since German/Swiss companies are still very used to the traditional degrees (and the MBF is just a recent "internationalized" adaption of a former degree) - the MBA is relatively new to companies on the continent. The only real pre-experience alternatives that are at least equally well respected are degrees from the LSE, Oxbridge and maybe HEC Paris (and these schools certainly carry the bigger brand internationally - but the enormous prize difference is only justified if you actually want to work outside German speaking Europe).