I looked around for a bit (probably not long enough), so I apologize if there is already an answer for this, and if so just paste the link and I'll stop bothering everyone.
I have a 600 EX RT-II (a second if needed) and 2 (4 if needed--my partner has similar equipment) 430 EX II (no RT).
To make a full up radio based system, what are you recommendations for Canon RT slaves that would fire the legacy 430 EX IIs.
I think that's it. I guess the receivers need to have E-TTL and manual modes. I've seen some recommendations and solutions at Photo Expo Plus, but there seems to be a lot of them and keying in on the best prices/quality seems to be kind of challenging as I've never owned any of them and it seems everyone has 1 idea or another as to which ones work better (I guess that's being a salesperson).
Anyway, your feedback is appreciated!