Sony provided an update to 6.0.1 I did not think the bloatware was as bad as a carrier-branded phone and most of it appears easy enough to delete. For a personal phone, I'd buy the Z3C again. (For my second, work phone, I liked the Z3C enough that I decided to go with a Z3, which I also like.)
On the Z3C, the Sony bloatware is bad. Apparently they've reduced it a bit since then but I haven't gone back. The hardware is nice, it's a shame they have to ruin it with crap.
I fiddled with various settings, and I think managed to disable almost all the bloatware. I get a notification about every two months that Sony's updater needs an update.
I'm pleased with the phone otherwise, and would buy it again.