I am currently taking the course and just now entering the second year. I have to say that it has stretched me, but I made the commitment and I plan to finish and then take the Journeyman's course.
One problem I have had is that the assignments are due every two weeks, and sometimes that has been difficult. If you were taking a college course, you would get a break between semseters at least. There is no break, so you do have to keep rolling. However, my mentor has been very amicable when I have gotten off track.
There are some parts that I just hated--but I that's just me. I want to write what I like to write, and not have to write things that don't interest me. But I can say that I have become more disciplined and have a far better understanding of what I'm doing. Having a mentor has been helpful, but honestly I have learned as much from some of the other writers here. That too, could be because I don't email my mentor with every question, so I think how much the mentor gives to you is largely tied to the relationship you develop with them as you go through the course.
It is pricey, but I made choices when I started a year ago about where my financial commitment would come from (I pay monthly) and that too has helped me remember to stay on track and complete the commitment that I made to myself when I started. So my advice would be not to undertake the course on a whim, because if you do--you'll probably quit. You should be willing to make it a priority, just as if you were taking a college course. You do agree to pay the full amount of the course, whether or not you complete it.
The conference I hear, is top notch and the exposure is a great opportunity but it is way too expensive for me to even consider at this stage.
As far as writing opportunities, there are more freelance opportunites posted here than on the CWG website, and the CWG forums are not nearly as interactive, supportive or enlightening as the forums here. However, having to complete the assignments even on things I hated, has helped me recognize what I like to write and what I write best. When started, I just 'wanted to write' and now I know there are things I don't want to write.
The most valuable part of the course for me has been the emphasis on marketing, and my mentor has been very good at suggesting markets when he really likes something.
Overall, it's been worth the money to me. I feel like I've come a long way in the past year in understanding the business of writing.