Xtragrass is what was installed at the Ricoh when it first opened in 2005 so its been around for a while and not exactly a new idea, the fact that everyone else seems to still be using desso despite xtragrass being available for at least the last 10 years (probably longer, I can't be bothered to look at what they did before the Ricoh) would suggest to me it isn't as good.
I'd guess the reason xtragrass is being used again is that a lot of the underlying work/structure may already be in place from before making it easier to install rather than using a different system which would probably have to start from scratch rather than xtragrass being better than desso.
I'm not sure if it will now have to be done differently to how it was laid in 2005 to accommodate both sports and the science has probably moved on since then as well making it better than the one that was installed 10 years ago but I'm not sure on how it will hold up.
https://www.pitchcare.com/magazine/plenty-of-xtra-grass-to-cut-at-the-ricoh-arena.html
Do you know of any examples of xtragrass being used as a dual rugby/football surface at a top/professional level?
I'm hoping it will be quality but if it doesn't last its going to be an absolute nightmare again like this season.