I've not seen any tracer mags for a G36 though....
Tracer mags can be ok but the BBs sitting in the hop will fade as they are not illuminated. I have an older G&P one which is pretty poor and a couple of the custom built Incentive Designs ones which are a lot better but still not perfect. It's a basic limitation of the design, as soon as the BB leaves the mag it starts to fade so the longer it hangs about in your hop unit the worse it'll get.