Help me buy flash.

[Buckster]

I find TTL most useful in run-&-gun situations, where I'm holding the flash in my left hand or using a bracket on the camera, and moving around a lot. For that, I use a short TTL cable.

When I'm working my lights off stands with modifiers, it means I've got time to dial in my lights and don't need or want TTL. That being the case, more expensive TTL triggers are overkill for my needs.

Nonetheless, it can still be done optically, triggered via Canon's Master/Slave TTL system. I don't know the specifics of the body pixelrabbit uses, but if nothing else, the lights themselves will do it with one of them in the camera's hot shoe acting as the master.

Agree, the only thing I have to add to that is if you use your TTL triggers in your studio situation listed above you can change the zoom and power of the flash from the camera which might save you opening your light modifier or having to lower/reach your lights.

I've actually done some TTL work in-studio in the past, using both the ETTL capable Canon and Yongnuo Flashes, 7D popup flash as master or ST-E2 Commander on 5DMKII, using Canon line of sight or ETTL Radio Popper triggers.

I didn't personally find any of it to be that much more convenient, even being able to work it from the camera, and prefer to just go manual, which is why the entire Radio Popper set I have (and probably the ST-E2 as well) are about to go up on eBay.

All the modifiers I use with speedlites provide quick and easy access to the speedlite controls, so that's not been an issue for me. Also worth noting, in studio situations, once you've got your settings dialed in for a particular lighting situation, it's a simple matter of writing them down to recreate them again later without having to experiment or dial them in again.

But that's just me.