Hi, welcome to OSBot.
There is really only one main difference between reflection and injection bots. An injection bot modifies the game code and allows the bot to access more information. The only potential benefit of using a reflection bot is that it does not modify the game code and that could theoretically remove one avenue of detection.
There are techniques one can use to make injection less detectable while maintaining the benefits of using injection (this is what OSBot does).
Tl;dr both are detectable and both can get you banned, we don't know exactly how Jagex bans so we can't say if using one over the other is better.