Coasting ticking sounds vary a lot. I haven't ridden a SunRace cassette but do have three SunRace freewheels. They all run much more quietly when coasting than my Suntour and Shimano freewheels and cassettes. No problems in actual use.
My 10-speed Shimano cassette on an aluminum semi-aero wheelset emits louder ticking while coasting than my Shimano and MicroShift 7 and 8 speed cassettes on low profile aluminum wheels.
If you're accustomed to the loud ticking of current Shimano and other brand cassettes, amplified by the resonance of carbon wheels, some other cassettes and/or freewheels will seem oddly quiet, especially on low profile aluminum rims.