BRF, I can't say which color is better, but the I-nymphs I prefer to buy look similar to this one....
Reason being...I found an Isonychia crawling on a rock in the North River one day, and on the way back to camp, I stopped by the Green Cove market and found a pattern similar to the one pictured above. Until I lost it to a vicious tree a few weeks later, I had great success with it.