This is the 3rd one of these I've bought along with the ST-E3 controller, that should tell you something right there! It's great that all 3 are adjustable right from the camera.

RADIO CONTROL

A little pricey; but worth it

I have only had a small chance to use this, but so far I love it. I have a 5d Mark 3 and the camera will controle the flash through the menu. It is nice to have a flash that will work with the full range of my 70-200mm lens. The only down side is the price, but Canon had $50 off.

Easy To Use; Fast Recycling; Powerful Output

Heavy

Simply the best flash made by Canon and the right way to go for professional use. If your not making money off this unit you could step down a model but if your going to step up and start making money this is your model.

Works well as the primary flash in the Canon system. Now if they will come out with smaller RT flashes, things will be complete.

Consistent Output; Easy To Use; Fast Recycling; Powerful Output; Versatile

I am still learning, having shadow issues

Lightweight; Powerful Output

I use this for my photography

I use flash for low-light portraits and product photography. This superb unit has everything I need and more. Several weeks after acquiring it I am still discovering its incredible flexibility, and you could be forgiven for assuming the controls will be complex.

None Discovered So Far

I have owned the 430EX II and the 580EX II. I have used PocketWizards, Cactus triggers, and the built-in transmitter in a 60D. None of these solutions worked 100% of the time and all had major downsides.

Amazing Flash, don't be fooled. this flash is the cream of the crop, so don't settle for anything less. if you do, its your own fault. lighting is the the key element to photos, so why would you go with anything less then the best?

Excellent! Very versatlie and multi-use flash - perfect for almost any situation and covers Canon's low-light deficiencies perfectly! top-notch prodecut and a very competitive price!