I probably should have been clearer than '+/-'. What I wanted to verify was that it could provide dual polarity, supplying both + and - voltage to, say, an op amp. It's pretty clear to me now that it will be able to and not have any bizarre hidden gotchas in the design or user interface.
I was just being overly cautious since I was about to order the Siglent, which I've now done.
I'm pretty new to electronics. I was going to order the Rigol DP832 but then I decided that the floating outputs on the Siglent were worth more, to me at least, than any other advantages of the Rigol.