Welcome to the forum. While a Cobb Accessport doesn't do for our little FiST what it does for the BMW 1-series N54/N55 engine (you are very lucky to have an engine SO responsive to mods!!), the mods we do to our cars do make a notable difference.
135i - Cobb AccessPort +100hp +120tq
- aFe Intake +25 hp
- Exhaust +22hp
lol
Fiesta ST - Cobb AccessPort +5hp +30tq
- Intake Tube / Filter +8hp +9tq
- Exhaust +12hp
yeah we don't compare so well to response to mods, but they're wholly different animals made to different price points- and entirely different engines. I'd absolutely have both if I could.
and whether you need Fiesta ST parts or parts for your 1-series hit up ModBargains.com (where I work) - the guys here are amazing with BMW stuff.
Good luck with your hunt, I am sure a test drive in a Fiesta ST will likely have one in your driveway!