I'm currently enrolled in the second Solaris 10 Admin course part 2 and took part one last week. I am not impressed. I took a redhat course a few weeks ago (RH-133) and was much more impressed by the quality of the instructor and layout of the training/labs. I am taking these as a refresher, since I haven't messed with Solaris much since 8. For the money, I would recommend getting a book and spending the time reading and loading/configuring it.
When I got the courses, I also grabbed a few cd courses (one for me and another for a friend). I wasn't overly impressed with those, but after attending the class, I can say they are pretty much on par.
Just for some info:
Sun course, approx 4k(us) each (5-8 ppl per class)
RedHat Course, approx 2.5k (us) each (18 ppl in class)