Good experience on the 457 for us. Myself, wife and the 2 kids have been on it since June 2011 and are going through the process of obtaining PR through my employer (RSMS). We haven't found it restrictive and it definitely offered us a cheaper, fast and easier route to Oz. I see you're coming from the UK so you should be entitled to reciprocal medicare which is good. This may not be relevant, but bear in mind that if you are planning on seeking finance (car for example), the length of the finance agreement can only be within the term length of the visa (based on my own experience). Good luck.