There is more to an uprated air filter, intercooler and exhaust than just another 25bhp for 2,500 Euros.
There would not be a huge amount between a 300bhp car and a 330bhp car performance wise, but the 300bhp will not breath as well, sound as good or reduce inlet temperatures enough to stop higher levels of heat soak (power loss). The 330bhp would be faster though if you were that worried about it.