No expiereance with a FS280. With that said most trimmers, saws, etc run projected tip plugs and for good reason. BRH6IX is not a projected tip plug.
Tuning changes by the day and has nothing to do with changing plugs.
I live in a tropical climate so no, the weather over here is consistently hot. Switched back to a new stihl ngk copper just to verify and it ran too rich.
I like the throttle response it has on iridium. In my country the oem stihl plug is almost as expensive as the br6hix.
The same type of iridium plug was also ran on a stihl blower(sr430) that ate through oem stihl plugs in 4 tanks. Iridium lasted around 40 tanks before it burned, dealership over here couldn't figure out what was wrong with it so this was the solution.
I once ran the br6hix on a ms250 chainsaw as well but the air cleaner doesn't seat properly due to lack of space.
Projected tip for good reason? In 6 years of hard daily usage i would have noticed the drawbacks by now don't you think?