For the professional engineer, the advice remains consistent: The safest, most reliable way to run Pro Tools is always the legitimate, authorized version with an active Avid support plan.
The R2R releases are famous in the audio community for their quality. Unlike "cracked" versions that might crash or install malicious software, R2R takes pride in technically bypassing the protection without altering the audio engine. They effectively emulate the license response, tricking the software into thinking it is authorized on an iLok dongle or cloud session.