Hello!
Today, the same day as Oracle announced that they are retiring 1Z0-815 and 1Z0-816, I passed 1Z0-815 with 85%.
Here's how I did it:
1. I bought Boyarsky and Sellikoffs' study guide and read each chapter. I took notes and did all exercises after each chapter. It took at least 1-2 days per chapter.
2. I used Sybex to try practice exams and failed really hard. One thing to note about Sybex questions are that they are way more time consuming then the real exam. So, if you don't do well on them, don't worry.
3. I used Whizlabs exams to get a feeling. One thing I learned about them is that they are very API specific. More then the exam. And their focus is memorizing. Furthermore, Whizlabs has a few questions unintentionally wrong. No worries. Everybody makes mistakes, right? What disappointed me with Whizlabs was that they did not correct these mistakes even if users have reported them (for example, in a question it was written Listlst instead of List lst, leading to code will not compile option. Multiple users reported this months ago, but no change). Still, my last Whizlabs I failed with 61%!
4. Last, I tried Enthuware and liked their questions and explanations. Here is how I scored on them: 55%, 69%, 77%, 74% on the first five and 69% on the Last Day
Test. Really, Enthuware is excellent to sharpen your skills at the end. And it was cheap too!
I went into the test hoping to just pass and it went better then I thought. Thank you Selikoff, Boyarsky, Whizlabs and Enthuware!
Now I must take 1Z0-819 a couple of months in the future..