I found another very nice review of DrJava  by a student taking Csc101 at an unnamed university:
Our teacher let us use Dr. Java as a working environment for our Computer Science 101 class last semester (S.Y. 2008-2009). So far, it is the best programming environment that I’ve used. I have tried Turbo Pascal and Borland Delphi when I was still in high school. Though they are very easy to learn and good for beginners, their functins are quite inefficient in the long run. There are a lot built-in functions in Java that can’t be found in Pascal and Delphi.
Though Java has several programming environments, I find Dr. Java as the easiest one to use since it is so quick to debug the codes. In the ‘Interactions’ pane, I can easily test whether my program is doing what I want it to do. Also, I can easily determine whether a compile-time, run-time or logical error is occurring.
Dr. Java however, is limited to some programs related to recursion or looping. As what my teacher explained, Java could not hold such functions because it already involves filling in memory of the computer. If the program gets heavier as the loop runs all throughout, the process becomes slower.
Despite this, Dr. Java is one useful tool in object-oriented programming (this is so far, our topic in CSc101). There is a display pane where I can access the previous classes that I want to connect with the one I’m working at. Handy at only a small bit size, I have a copy of it in my flash drive. It’s going to be useful especially now that I’m taking BS Computer Engineering course. =)