I have some Viperspectra xs 2000s 270 watt draw and they work great, the diodes are Samsung and the driver meanwell so I think they are great value for the money the build is good and the dimmer works great. Looking at the par map it appears the XS2000 gives higher numbers than the KS3000.
To me if the running gear and diodes are top quality then the cheaper LEDs are fine, in Australia the xs2000 is $200 cheaper than ks3000 for 30 watts difference.