Today I took the OCAJP 7 and passed with 83% at the age of 13!
I studied for around 2-3 months of 2 hours per day, using the following materials:
-Mala Gupta's Java SE 7 book
-K&B OCAJP 7
The exam was actually pretty easy compared to what I had thought. I've heard everyone say that Enthuware was slightly harder than the real exam, but I didn't know by THIS much.
I had initially finished the exam in 1 hour, but I had a lot of questions marked for review (~25?) that I was either unsure about, or I thought I could have been careless with.
After the last hour in which I checked most of the marked, I had 7 marked questions, but I could not go over them since I had only 40 seconds left.
Overall, I'd say this exam was a great experience for me, and it was worth the time of studying.
Thanks to everyone on this forum!