Metal dents & scratches easily, and has a higher heat transfer than FG doors.

My advice would be FG with gel stain that when properly
applied looks like wood.

best of luck.

If you are using a storm door, make sure it has operable panels to vent. You'd be surprised at how much heat can build up between the entry and storm door with non venting storm doors even on moderate, sunny days southern exposure. Heat can be real hard on most any entry door type.

Strom doors can actually help warm the house when facing south as a passive solar effect entry door open on certain days of the year. All dependent on your geographical location.