I don’t have any reason to change for a system which is heavier, more expensive and doubtless harder to index properly and reliably.
As said previously there’s no way it’ll be heavier, even looking like for like. I’ll wager that XX1 cassette will weigh less than a 10 speed SLX.
More expensive? Yes, probably, although one less shifter, mech and chainring. ‘Plain’ rings are dirt cheap too compared to ramped multi-rings, dunno about this ‘special’ one though.
Harder to index? It’s one mech, with one button for ‘up’ and one for ‘down’, the fact there are 11 will make it no harder to do, by not needing to do a front mech as well it will be far simpler. Fewer moving parts/pivots/rings getting worn. Makes sense.
I like it! Reckon 10-36 would do me, with a 34t, or 11-40 with a 36t but I guess they’ll offer options.
Considering how expensive XX/XG999 cassettes are I think it’ll be priced in the ‘hilarious’ category.