mmm.....the RTi1 was a blind purchase for me. Flew to HK, almost got lost finding Rhapsodio. This was in 2014. The demo unit sounded superb so I got the RT1i. When I flew back home, it was just awful. The treble was piercing. So, I let it burn-in for a long, long time. Today, it sounded more like the demo unit. I love it. With the HM 901S, it doesn't sound thin to me and the bass quantity is just right. I'll probably get the version 2 at some point in the future.
Headphone Reviews and Discussion - Head-Fi.org
And it looks like RTi2 is worth the shot.