My Two penny-worth
Hi there
Ok I'm biased towards SA as I did my PPL here. The majority of my flying has been in Cape Town and at George. I have no concerns at all. At the major schools/flying clubs you will be treated fairly and have a great time learning to fly to a high standard.
Port Elizabeth seems to be a very popular destination and having flown there several times I can see why - it's just the right mix for a student in so far as it's not rediculously busy but at the same time there's enough traffic for you to need to keep your wits about you. I personally love flying out of Cape Town but I suppose that as student pilot you don't want your hard earned cash being eaten up sat on the ground for the best part of half an hour.
My only advice is don't part with any cash up front and beware of people selling you packages in the UK. You can search this forum and find out the pitfalls that can occur. Allow yourself about 6 weeks may be more for your PPL. How quickly you finsih obvioulsy depends on a variety of factors but the weather although generally good in SA can of course be frustrating - if you do finish earlier then use the time to explore the cape by air, believe me it's something you wont regret.
Good luck!