UVC certainly works, the efficacy of which is determined by output and dwell time, of which smaller handheld units typically fail to address. Ultraviolet Germicidal Irradiation Handbook is the definitive UVC tome and the primary resource I consult when specifying UVC kits for HVAC systems.
Yes but running a suction only hand held over a mattress isn't as deep cleaning as a main size vacuum cleaner - you can see the dirt in the canister and the Raycop model in particular - plus a lot of these hand helds are not suitably powerful enough on suction alone.
