"I feel it's due to the 120 TPI in the casing vs 60 TPI in the EXO." I think you're onto it with this. TPI has a big effect IME too.
@Onawalk: I reviewed the XC insert in 2019. A note from my summary below but I'll also say that further experimentation with more rims/tires shows much of the bead seal I experienced while working on that review was thanks to the Spank wheels (maybe it's time for an update to that review). With looser-fitting rims, there's little bead hold provided by the XC insert. I've used it since with Super Gravity and DD tire carcasses purely for a tiny bit of rim protection but with my usual pressures, any lower and I damage the rim through the insert while losing support from the tire.
"…this smaller, lighter-weight version strikes a great balance for riders looking for rim/flat protection and firm hold for the tire bead. The trail damping effects are less than the original and I found I couldn’t lower my pressures the same amount but they still offer peace of mind on the trail."
[https://nsmb.com/articles/cushcore-xc-tire-insert-review/](https://nsmb.com/articles/cushcore-xc-tire-insert-review/)
April 16, 2021, 9:57 a.m. - AJ Barlas
"I feel it's due to the 120 TPI in the casing vs 60 TPI in the EXO." I think you're onto it with this. TPI has a big effect IME too. @Onawalk: I reviewed the XC insert in 2019. A note from my summary below but I'll also say that further experimentation with more rims/tires shows much of the bead seal I experienced while working on that review was thanks to the Spank wheels (maybe it's time for an update to that review). With looser-fitting rims, there's little bead hold provided by the XC insert. I've used it since with Super Gravity and DD tire carcasses purely for a tiny bit of rim protection but with my usual pressures, any lower and I damage the rim through the insert while losing support from the tire. "…this smaller, lighter-weight version strikes a great balance for riders looking for rim/flat protection and firm hold for the tire bead. The trail damping effects are less than the original and I found I couldn’t lower my pressures the same amount but they still offer peace of mind on the trail." [https://nsmb.com/articles/cushcore-xc-tire-insert-review/](https://nsmb.com/articles/cushcore-xc-tire-insert-review/)