Personally, I'm not a big believer in major warmups. I do believe in playing a little bit before going on stage, or before the rehearsal starts, if for no other reason than to remind myself what key the trumpet I have in my hands is in.
I DO strongly believe in blowing warm air through the horn prior to an entrance, or piror to tuning, so that the horn is at or close to operating temperature so that my intonation is easier to cope with.
More than a little bit of playing as a warm up can use energy that might be better spent on the concert itself.
My two cents, anyway!