Hi guys,
I have an SB600 but want a second off camera flash compatible with the Nikon CLS.

I can't stretch the budget to an SB900 so the alternatives seem to be the Sigma 610DG Super, the Nissin di866 or considering its not that much more from HK, the SB 700. Ebay prices seem to only be a difference of about $70 between the Nissin and the SB700 with the Sigma in between.

I know someone is going to ask what I want to do with it, well, no particular plans but would like to use it in a small indoor studio using the SB600 and it as my main flashes and I'll be adding a cheap Yongnuo non-ttl as a background flash in its 'S2' mode (I think).

I get the impression they can all act as master to trigger other CLS flashes (but how successfully?), they can all act as slaves and they all have similar zoom capabilities (with the SB700 I think a tad better).

The Nikon specs mention the SB700 has a 'condensed' Master function, but doesn't go into detail in what way it is 'condensed'. Any ideas?

Opinions (particular first hand) would be great.

Thanks