Yes, you can probably move to a better location after a year or two, but at the moment moving to Australia is effectively a one way ticket.
DD works in a relatively unpopular, largely rural, deanery. Most of her peers are local and studied at the local medical school. (Studying in England is a lot more expensive.) Going to Australia for a year or two post F2 was effectively a rite of passage, and an opportunity to have some different experiences. Some stayed but most returned.
Now it is an emigration decision. You can't get back. The Deanery really needs doctors who are happy to work in rural locations, who understand the local population, and who would expect to stay and build and continue their careers. But though health policy is devolved UK immigration law is not, nor are allocations for specialist training.
Already, because overseas recruited doctors often don't stay, Trusts within the Deanery are having to recruit from overseas all the way up to Consultant level. At this point a lack of NHS experience is a real disadvantage. As mumsneedwine suggested it is then not unknown for an F2 to have to question decision making of much more senior colleagues. I am now bending everyone's ears, so was recently talking to a Philippino nurse who has been in the UK for 22 years. He first complained that some newly recruited overseas nurses appeared to be lacking key nursing skills (catheters, cannulas), and then described having problems with a doctor who would not listen to a nurse's concerns about a proposed prescription. Worried that the proposed medication would kill the patient, he phoned the pharmacist and briefed him. The pharmacist then quizzed the doctor and refused to prescribe. The same nurse confirmed that a big lure was UK experience and British citizenship. This then enables much better salary rates in the Gulf than would be the case if you go directly from the Philippines, South Asia or Africa. So the UK becomes a training ground for overseas health sectors with the constant churn doing real damage to the culture, traditions, and long term viability of the NHS.