Well...Un surprisingly more money does mean better parts. I would at the very least HIGHLY encourage the P5i over the P10 - largely for the fact that it has an IGH and a belt drive- both no brainers for me! The S00 is a pretty big jump up again but if you plan to put this bike through it's paces I would save the S00 is undoubtedly worth it if you budget allows it! The Enviolo hub is frankly incredible and the brakes...you really will feel a difference, but this *even* comes with the upgraded headlight plus the thud-buster seatpost. All of these feature are right in your face during the riding experience - so if you plan to ride a lot...this will only encourage you to ride more! And of course both models you mentioned are both IGH plus belt driven so they are as a baseline great options!