Yes, I do. My (first) master's was more focused than my undergraduate...I studied a narrower field in more detail...and was frankly more useful. I found that my undergraduate was targeted toward getting a basic knowledge in a large number of topics that there wasn't enough depth in any one to provide a useful problem-solving toolset.
For me, the degree was definitely worth it...
I should mention that I am a EE, so the above may not be applicable to MEs.