I will go a large step further to state that "the brain" is not nearly obvious and most definitely can kill if you go left. The left side (imo) is one of the ugliest rapids on the front range. The only way through is on the right which would be very difficult if you didn't start from that side VERY early on in the rapid.
I would highly recommend a guide.. if for only that rapid. It's basically just a class 2 lead in that is very difficult to tell where the horrizon line is until you are deep into it.
Beyond that rapid and Bridge which is a very obvious horizion line, the whole runs really is wonderful and not overly difficult. A class IV creeky feel and good wilderness run.
"Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body. But rather...To skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming... WOW !!!! What a ride!!!!!!"