The next one is the Rigol DP 811 (195W) (not A) i have seen Daves Review of the DP832 and wanted to go with these. But you can't Bridge them that it will provide the Current i need. So i looked at the DP811 the Power Supply will cost me in Germany 522€ including Tax.
The DP832 output 1 en 2 can be parallelled according to the user manual (see chapter 2-9 in the user manual): https://www.batronix.com/pdf/Rigol/UserGuide/DP800_UserGuide_EN.pdf
I just gave it a quick try on mine, works ok (see pictures). With no load attached, there is some current indicated that is not present. Also, when one channel is not actively supplying current, the measured current is a bit off. As soon as both channels actively supply current, the current measurement is correct. I increased the voltage gradually until the switch to constant current mode was made. This worked as expected.
So when you only parallel the channels because you need more then 3A, this should be quite ok. So if you need this high current only occasionally, this seems like a reasonable solution (it would be good if Rigol would provide a "mode" for this, so the display could show the total current instead of the 2 individual ones, and the same for the limits).