My opinion and 2 cents worth:
SP01 series are all good, just progressively more done to them from SP01, SP01 Shadow, SP01 Shadow target. The rail on all of them ads the weight for competition to stop muzzle flip. The main jump from SP01 to the SP01 Shadow (not to be confused with the CZC Shadow which as I understand it is a tuned 75) is trigger adjustment, reset etc. Jumping to the Target ads bushing etc for accuracy beyond a normal shooters abilities (at least mine ;-)