i did i a couple years ago and did ok at it, problem was when i went on holiday, when i got back i just didnt have the self discipline to get back to it so i joined a class, and that suited me better at the time. do it at home on my own now (with the support of friends on here of course).
I wouldnt say any one way of doing it is better than the other, its what suits you best,but they all work.
To be honest I dont think its worth the money. If you have the discipline not to need classes save your money and use Minimins instead. I got a free trial for the online one and thought it was really poorly done