Not necessarily, and you often get what you pay for. If you're to offshore your online advertising, even to a first-world country like England, and paying top dollar, you'll still get a mismatch in culture, use of language and key word optimisation. Ads are highly related to keyword research. For example, The English call it "sun cream", not "sunscreen" and therefore wouldn't think about the word sunscreen. They'll also write content that can just sounds odd occasionally to an Australian reader. Still, offshoring to England is a great option, the competence is often high. The real key is to evaluate their education system. If it's not great, and if it's not I.T focused, it's likely you'll get a poor, or damaging result.