I highly recommend having a guide. Although I have done it once, I wouldn't go back in there without a guide for at least 2 or 3 more times. The moves are fairly easy IV+, but a swim is destined for dangerous/deadly sieves that are literally everywhere.
Also, pay attn to the flows. I have been told that over 1K starts to jump into a much tougher run as well.
It is really beautiful in there... a true gem of a 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!!!!!!"