Performance wise, there is zero difference, imo, between my r7020 and r8000 bikes (shifting that is, the hyd discs are def better, which is why I'm building a new road bike lol). But I can feel differences in the shifters (mainly, rough edges on the 105). For the new build, I went with r8020, I could justify $200 more over 105, but couldn't justify another $400 over that for DA. Plus, DA deserves a better frame. lol