Oilpump 6.1, any better than stock?

i just ordered the Melling 10342. It is not a HV pump but offers to replace the Bypass spring to maintain the pressure. It is here in Germany for EUR 210 which are approx 230 USD. (incl shipping and taxes )
My best Quote for a OEM pump was EUR 450. This is more than twice of the Melling .....