Long term or repeated exposure to peroxide sounds like a red carpet for oxidation to me. Sterilization (=really getting rid of all the germs) is fiendishly difficult if you don't have special equipment such as autoclaves/UV-C irradiation after ultrasonic cleaning. And it's not possible to keep the equipment sterile anyway, unless you can immediately package it in a sterile wrapper under controlled conditions.
I only use my own razors, if I'd use someone else's I'd first dunk it in ethanol/isopropyl alcohol and wipe it clean. But I doubt that's necessary, when allowed to dry there's few bacteria/viruses that survive exposure for longer than minutes/an hour tops (assuming nothing like anthrax is present of course but if it is you'll have other worries). If you're shaving and were to swap razors during or immediately after a shave that would be a different matter. And oh yeah, many barbers test positive for Hep A or C, for them it's a professional risk.