Hello. Its been a while since i've been here. I recently picked up 2 600ex-rt and the st-es-rt commander. I've not had much chance to play with them. I used one on camera for a recent wedding and did ok. I have 2 original 580ex flashes that I was using (not exII) and they still are in fine shape and was wondering if anyone knew if I could incorportate them into my kit somehow for bigger projects where I would want to use 3 or 4 speedlites. any thoughts on this would be great.