I got my full PPL in Australia some years back and converted it into a UK licence. Licensing rules have changed since I converted (in both countries I think) and slightly different situation (only being part way through training) to the situation I had. Therefore I would re-iterate the advice to do your homework on the bureacratic requirements first (LASORS is an excellent source) to ensure that you are sure about your prticular situation. I have personally always found "Flight Crew Licensing" department of UK Civil Aviation Authority very helpful when I have needed to contact them. (Small tip on finding your way around the CAA website - all these types of issues come under the Safety Regulation Directorate...)
A few further thoughts, though, which may be useful based on my experience:
- do not bank on doing a PPL in the minimum number of hours! These really are minimums not averages...
- Australia is an excelllent place to do flight training - the standard of General Aviation there is very high and an Aussie PPL always used to be extremely similar to a European one: puttting aside whatever the licensing rules are, therefore, the actual flying you would do there will stand you in good stead for the requirements of the flight test in UK.
- Do not forget ground school/theory exams - check these out in LASORs as well. I did not have to do the full set of exams again when I came back to UK but not sure what rules apply if you do not have a PPL already from Australia. You will need to do at least some of these to go solo and will need to retake some of them back in blighty (and if only part-way through check LASORS but you might find you have to retake them all). Expect at least some duplication here. Exams/ground school may not be the biggest cost of doing a PPL but do represent a significant time investment and need to be taken into account. You might also have to buy a text book in each country for at least some of the subjects... Air Law especially always used to have some subtle differences between the two countries.
- I found converting to flying in UK relatively easy - the main differences are around navigating across country where you need to navigate through different airspace requirements and navigating across England feels very different to navigating across the outback - even though the principles are the same. Reading the weather also has its differences...
- RT (speaking on the radio) is also more different than you might expect between the two countries and you would need to re-learn some of the phraseology used. I did not find that particularly difficult but did need to be taken into account. As with much in flying, if you prepare and do your homework on the ground when you get to UK on this front then will not impact on hours spent in the air.
- Any switching of schools/instructors will probably add a little to the hours you need to do in practice as you will need to get used to a different approach. Unless very budget constrained this is not an argument not to start in Australia, but I would be aware that you might effectively add a small number of hours to the process this way. This also depends a bit on how far through the training you get in Australia. Basic handling and circuits (take off and landing) is pretty much the same - how and why an aircraft flies does not change with the hemisphere and I think the syllabus is pretty much the same at this stage of training. As above, navigation does represent different challenges though, if you get to that stage in your training down under.
- Obvious point: but you do get different / wider experience if you fly in both countries which enriches your overall experience. I got to fly in situations and into types of airfield in Australia which I would be hard pressed to replicate in UK (and vice versa).
- You might also want to consider what aircraft you would learn to fly in each country - but cessnas and pipers are pretty prevalent as basic trainers in both countries. WWW makes it pretty easy to check out prices and types of aircraft available at different schools/airfields back in UK.
Hope that helps your deliberations and good luck!