I definitely recommend a professional driving instructor. As has been mentioned, it's not about driving - it's about driving the the correct way to pass the exam which is a very specific way that will be forgotten as soon as you pass. No one drives like that in real life.
The instructor will be able to provide tips specific to passing the exam, and will likely spot a few bad habits to keep an eye on. I think that when you're an experienced driver, it's actually more difficult in a sense because you've had years of accumulating driving habits that may be detrimental to your score from the point of view of the examiner.
Also, don't be deterred if you need to shop around for instructors. If it isn't quite working, try another instructor. Different people, teaching styles, etc. An instructor you really gel with is totally worth it. My instructor was male, and I had absolutely no problems. He was professional and friendly, and there wasn't any awkwardness. If she prefers to have a female instructor, that's totally fine, but from my limited experience, a male instructor can be just fine. (my instructor had immigrated to the UK several years prior as his wife was British; we swapped visa stories while practising!)