Experience with 10W RGB COB LED?

I'm interested in using one of these 10W RGB COB LEDs for a project http://www.ebay.com/itm/High-Power-10W-Super-Color-LED-Chip-RGB-Bead-Lamps-COB-for-Floodlight-Spotlight-/172345056417?

However there's not much info on these and what's unclear to me where are solder points and if it's common anode/cathode. Constant current drivers such as the sparkfun picobuck and those based off PT4115 require separate channels for each color.

All of the anodes/cathodes can be separated by cutting off the tabs on the sides. The first picture in your link shows it as common anode, but again you could just cut off that tab if you needed to.

For low side driving...
AMC7135's are cheap as dirt (use zener and resistor to keep Vcc in spec, and switch the low side, and they work like a charm. ) and should work fine, just keep the voltage they have to drop low. AMC7140's will have no problem with it.

Or you can use the fancier, more efficient switching drivers.