Hello Will,
Here are the highlights:
1. 126 questions/3 hours
2. I completed about 110 questions, my compiler was kinda slow that day
3. Most of the questions are "be-the-compiler" questions on lambdas and streams
4. You'd better to know by heart the main built-in lambda types and Streams APIs, and some practice wouldn't hurt either
5. Streams.peek() is not on the topics list but I had a few questions on it.
A small number of stream operations, such as forEach() and peek(), can operate only via side-effects; these should be used with care.
See for more details:
http://docs.oracle.com/javase/8/docs/api/java/util/stream/package-summary.html
Cheers,
Igor