NO GREASE!!!
I've had issues with rim grease melting in the hot Florida summer and fouling my plugs, I must mention this happened with the old formula No-Toil rim grease, I quit using the grease and have never fouled a plug since. I use No-Toil filter oil/cleaner, and filters on my bike. I also use Twin Air and Moose filters on my wife and kids bikes w/ the No-Toil oil/cleaner, if they are done every week the filters last forever. But don't oil up a filter and bag it as a back up, it will disintegrate if you don't use it right away. Just put a clean filter in a bag, keep the No-Toil oil with it, if you are going to need it that particular day, oil it up before the event, let it air out to evaporate the alcohol, and bag it up so it's ready when you pit.