Changed mine from standard to Cosworth and felt nothing - gave it a slightly different sound but marginal.
Spending £30 on an air filter, on a car running circa 250bhp on average, is not going to make a noticeable difference. I challenge anyone to tell me they can notice a 1-2bhp change on a 250bhp car...
...anyway, the car will reset to factory default power anyway, without the uprev, this will prevail over any power adding mods.