When I looked at going into this rabbit hole I had the same debate.
I went RimX because of the ability to play with the barrels myself, and the opportunity to go different calibers with a barrel swap, and the superior alum magazines.
I used the IBI barrel with a barrel nut, "like savage nut" and gave me the ability to tighten the barrel on a bit more to better match ammo choice. Plus I really wanted a 17 wsm. I eventually ended up selling it off and going to an anschutz I always wanted, as I could not source a 17wsm barrel. They are now more readily available and I might relook at this again one day.