I’ve heard all three but never in a controlled head to head or even at the same time. So it’s difficult to compare with any degree of accuracy. Each will obviously have similar house sound, and as you go up the ladder you’ll get "more" of it - no different than any manufacturer’s lineup.
That said, I believe there are some reviews (you’ll have to look for them) that perhaps indicate that the Elicit-R may be, if memory serves, a bit more forward than the Elex-R. Don’t quote me on that, but when I was researching them 1.5 years ago it seems to me that I saw something like that.