I haven't tried that fork but I did buy a Z150 for mine and I have been very happy with the ride. I rode the FXR in 5" mode for a year with a Vanilla fork and it was nice but I like the ride in 6" mode with the higher BB and beefier fork/slacker HA better. I was worried about the front end being too raked out but that hasn't been the case and the suspension feels balanced, plus I can lock the fork down for long climbs with the ECC feature. The thru axle with beefier front tire just plows thru the rocks, much less deflection compared to my previous setup, I imagine the 66 probably has better damping than mine too.
I have a Burner for XC riding so I've really enjoyed the FXR setup with beefier components, I say go for it.