For many moons, I saved for this kit. The ultimate solution!! And did it work great! You can have as many Speedlight's coupled to it as you like. You can vary the output of each one, which really gives you the ability to create your own little studio out in the field. I was not disappointed and used it to create thousands of photographs all well exposed.
There are two problems, however: One, the operating cost and two, it's extreme close-up capabilities.
1. The equipment only works with 3V non-chargeable batteries. Each one of them between R70 and R110 rand. And no, they do not last that long. I have tried various options in order to get the best batteries at the best prices, but with the money I have spent over the years, I could have had another prime lens by now.
2. The diffusers enable you to work quite close: up to about 50mm from the front lens element. The moment you want to work closer than that, you start to run into issues that have to be solved by some clever means. The implications are that I would not recommend using a macro lens wider than about 50mm (check the close-focusing ability) and that extreme close-ups are very difficult to manage with this system.
In conclusion: Yes, it is a great system for normal macro as long as you can manage the operating cost. For extreme close-up and where you need very close focusing ability, I would not recommend it.