As has been said make sure you visit both and decide which YOU prefer. Both Oxford and Jerez are regarded on par as the best in the world for JAA integrated training.
It is all down to what you like. Personally I'm not a fan of spain and so really wouldn't enjoy spending over a year there! I love the USA and so spending 5 months or so in Arizona is awesome. You also get to visit all the great places around it, LA, Vegas, Grand Canyon, San Diego, San Francisco etc. I think Oxford was an excellent school and as you say they have excellent stats for employment. They are pretty accurate too. There are only 4 people out of my course of 20 who don't have jobs 6 months now after finishing and 3 of those 4 people are in a hold pool waiting for a position (myself included)
Also have a look at the differences between the courses. One of the main reasons I chose Oxford over Jerez was how they do the ground school exams. Oxford do ALL of the exams first before you start flying. You spend 6 months at Oxford and get all 14 exams passed and then go to the US to do your CPL. Jerez only do half of the exams before they start flight training. Having done all the exams I know that I want my FULL attention on the exams and not to have to worry about learning to fly whilst trying to pass the exams. It also means that when the exams are all passed at Oxford you can fully enjoy the flying without worrying about exams!!
Both are excellent schools, just visit them both and decide which you think will suit you best. Good luck!
