My suggestion would be the Yongnuo YN-E3-RT @ $125. Does everything the ST-E3-RT does plus you get wireless 2nd
curtain sync and the ability to use <Gr> mode with older DSLRs and it has a some what usable focus assist beam. It
does not have weather sealing, it will drain your batteries if you leave them in while it is not in use and it will not wake the
Slaves from time to time but these are all easily delt with.....do not use in wet weather, remove the batteries when not in
use and a quick off then back on of the power switch restores full functionality.