I am writing to ask if anyone you have any experience with this Flash, Canon Speedlite 470EX-AI, Auto Intelligent Flash. If so what is your thoughts about it. I am in the market to purchase a new flash for my Canon 5D mark IV.
Can you help?
Personally, I wouldn't buy the 470EX-AI.
The main claim to fame of that flash is it's "auto bounce" feature. I believe that's what the "AI" is all about. But I use bounced flash as little as possible and mostly only with a bounce accessory such as https://www.bhphotovideo.com/c/product/833255-REG/DEMB_CLFI_Classic_Flip_it_Reflector.html
or, with my more powerful studio strobes, bounced out of of a large umbrella.
The reason I avoid bouncing off ceilings and walls is because you're at the mercy of the ceiling or wall being close enough to work with, it's very unpredictable, is usually a huge waste of flash power that makes for slower recycling and very often causes problems with color tints due to the colors the walls or ceiling are painted.
Direct flash is a lot more efficient and controllable. If the user finds it too harsh, direct flash can be modified in many different ways with a variety of accessories.
Another consideration... I haven't been able to determine how the 470EX-AI communicates in multi-flash setups. If it's able to do so at all, I suspect it's optically controlled (near IR light), which requires line of sight setup, has limited range and can be influenced by ambient lighting conditions. The Canon "RT" or "radio triggered" flashes are much better for multi-flash work... using radio to communicate they don't require line of sight, are generally more reliable with a little more range. If only ever planning to use the 470EX by itself... might be fine. But if you might some day be interested in using multiple flashes or even just a single one off camera wirelessly, the 430EX-RT or 600EX-RT models would be a much better choice. There have been several subsequent versions of the 430EX-RT and 2 versions of the 600EX-RT.., the latest of which are still available to buy new.
The main difference between 430EX and 600EX is their size and power. In the past Canon's naming convention of their flash had to do with the guide number. The 430EX is rated 43 meters, while the GN of the 600EX is 60 meters. (With their latest EL-1 and EL-100 flashes Canon has stopped using this naming convention. I also don't know if the new flashes use radio or optical communication.... or very much about them at all.)
Other differences include that the 600EX-RT can function as either a master or a slave unit. One that's mounted on the camera hot shoe (or attached to it via an off-camera shoe cord) can control other flashes off-camera via the radio. The 430EX-RT can only
act as a slave flash. Canon also offers a ST-E3-RT Speedlite Controller, which can control multiple off-camera RT flashes if you don't want a large 600EX on the camera itself. (There's a different ST-E2 for the "non RT", optically controlled flashes.) Some cameras have optical control built in (using their built-in flash, so not a 5D model). A few Canon also have radio flash control built in (just the top-of-the-line?).
Another difference I've personally found important is that the 600EX-RT have a socket built in to allow use of an external power source, making a total of twelve AA batteries available to the flash (4 in the flash itself and 8 more in the external power pack). The 430EX models don't have that socket, so cannot work with the Canon CP-E4 Compact Battery Packs. 430EX can be made to work with some 3rd party external power sources, but it's a permanent modification. The external power packs make for faster recycling, as well as supporting longer continuous shooting sessions (though you have to be careful about overheating the flash).
Godox and Yongnuo both make very similar flashes and components that cost a lot less than Canon OEM and that many people appear to be happy using. Many other manufacturers make flashes compatible with the Canon ETTL system.
Again, I don't know much of anything about the new Canon "EL" flashes. I've only used several generations of the EX models.
The 470EX-AI appears to have been discontinued and not replaced by a new version. (It is still listed as available direct from Canon, but isn't avail. at retailers.)
The 430EX-RT III and 600EX-RT II are both still being offered new.