Like has been said the US will be quicker. But I don't think the UK is prohibitivly slow. I started my PPL at the beginning of October 2004 and I now have 39hrs TT and am just working towards the end of it, hopefully by the middle of March.
I decided to do my PPL in the UK because I would much rather learn to fly in the place where I am going to spend the majority of my time flying. I will be going out to the US to do my hour building and so will get to see what flying in the US is like compared ot the UK.