We're preparing to paint our garage door. It isn't peeling but we want it to more closely match the house trim color. I have Rustoleum High Performance Metal Primer and Zinnser 123 on hand. Which would be the best primer to use?

Before I knew better, I painted our house trim with Behr satin exterior latex paint. It has held up pretty well considering our very hot, dry summers. I've been reading threads that recommend 100% acrylic paint for exterior paint jobs. I would like to use the satin latex paint in order not to waste it and because our budget is very tight. However, it's important to me to do the job right the first time. I don't want to have problems with peeling paint in the future. Would the Behr satin latex work just fine as long as we clean and prime properly or would it be wiser to invest in a gallon of semi-gloss Acrylic paint? If so, any particular brand recommendations? Locally, we can get Benjamin Moore, Sherwin Williams, Frazee, Vista. (I also have some Rustoleum Industrial oil based metal paint on hand if that is a better option.) Thank you.