The best replacement for sb600 is sb400.

The best alternatives to sb600 are rated as following:
★★★★★  sb400
★★★★★  sb800
★★★★  sb700
★★★  sb900
★  nikon sb800
★  sb28
★  sb750
★  430ex
★  nissin di622
★  nissin di866
★  lp160
★  nissin
  sunpak pz42x
  built in flash
  di866

Your alternative for sb600 is not listed? Suggest!
Speaking about sb600, one probably shouldn't forget about pocket wizard.

Other search terms related to sb600 and their ratings are:
★★★★★ pocket wizard
★★★ d90
★★ d5000
★ d700
★ d60
★ nikon d80
★ d3100
d80
You have in mind a companion for sb600 and it is not yet here? Propose!



Google Trends

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sb600
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