Hahnel Tuff TTL..
I don't use flash a lot and have preferred to use a tripod with reflectors etc in circumstances where a flash might be the obvious solution. When I do use flash I try to bounce it etc.
Now, as to multiple flashes, I've used it a little in the distant past with cords, slaves and all that kind of thing.
On Saturday I'm photographing my daughter's wedding (I've done odd ones over the last 30+ years, but only for relatives and friends) in a venue which in bad weather will not be great (Superb outdoors) but the weather has been shaping up very badly, with gales and rain forecast.
I've three flashes for my Canons, a twin-headed Metz, a Canon 600rt and a Sigma Canon job.
Looked into getting a second 600rt and a transmitter. Too late.
Dug out my old slaves. They no longer work (no idea why).
My cabling not adequate.
What to do.
Internet dig. Could get Hahnel Tuff TTL transmitter with two triggers.
I did yesterday.
When I EVENTUALLY realised that the transmitter was on backwards on the camera (good design would prevent that) it worked a treat with both bodies (1Div and 1Dsiii (they don't have 1Dsiii listed as compatible, but obviously an oversight) and both flashes.
It is very easy to set up and will work at big distances.
I've a simple reflector on one flash and a handkerchief over the other. I tried straight on unreflected flash but too harsh.
I'm now looking forward to the challenge. Will spend the afternoon practicing.