Thank you all, much appreciated.
One of the big upsides of having the flash and diffusion sorted on the MP-E is that it gives me the freedom to take pictures knowing I that side is sorted. Since then I can take my time and try to get decent composition etc. I guess it is a confidence thing.
Having said that this one (or ones like him) have been on one of my newer plants and the flash did not allow me much room to manoeuvre, but on this occasion I held the leaf in my left hand and presented the camera and was able to find the beast in the viewfinder, which can be fun at 5x.