Early in my hi-fi venture, I lived with a pair of Infinity RS1b. Infinity was Arnie's company before Genesis. This speaker had given me lots of enjoyment but some headache also. The highs and midrange were excellent though I can't compare meaningfully with my current S5 as they are so far apart in time. Eventually I found I was not able to integrate the bass column. I also doubted that the bass servo was not speedy enough and often did more harm than good.
Borrowed RS1b image
I also had limited experience with the Infinity IRS Beta and the Genesis II. They were better but (to me) still had similar problems, though to a lesser degree as the RS 1b.
Like Adam, I also came to the S5 from Wilson’s Sasha.