Here is my experience with an AT&T Nexus 6:
I purchased a Nexus 6 via the AT&T web site (Blue/32GB). The site told me it would ship between Dec 24th and 29th with 2 day shipping. It was on my door step today (26th).
I logged in, set up my Wifi and it restored all my programs, launcher icons and widgets (Redbox doesn't support Nexus 6 - booo). I called the customer support number listed in the directions and they ported my number from my HTC One M7 in 2 minutes (10 minutes on hold).
The Nexus 6 came with Lollipop 5.0.0 and the update function said I was current. I unlocked my bootloader (should have been the first thing I did since setup re-ran and had to re-download all my apps - no big deal really) and sideloaded the 5.0.1 update using the following site:
m.androidcentral.com/android-501-ota-links-are-starting-surface-heres-how-use-them
The only bloatware I saw was something call "AT&T Live" which was a menu and loader for all the other AT&T software and a "myAT&T" app. I went to Settings, Apps and uninstalled AT&T Live, but chose to keep myAT&T.
Other than the AT&T logo and sound at boot up and Death Star logo on the back, I don't see anything other bloat/branding and for the ease of payments vs. upfront cost, I can total live with those.
Totally understand. I was ready to order from Motorola today, but DH came home and "talked me down." I ran the numbers for (1) a 2-year plan, (2) AT&T's "Bring Your Own Phone" non-contract plan, and (3) an AT&T Next plan that the saleswoman at AT&T really tried to convince DH to buy. The most expensive was the Next plan, then buying our own phones and going with AT&T on a no-contract plan, and, finally, the least expensive (only slightly less than buying phones outright) was the 2-year contract. After two years, I think we'll switch to the no-contract plan, if that's still available, for as long as we are using the new phones we're getting now. We are sort of tied to AT&T for a while yet, as we keep my parents on our AT&T plan and they would not adapt well to starting over again with a different phone. So we're committed to AT&T until that is no longer an issue.
I'm still kinda disappointed not to be able to buy the unlocked N6 from Motorola, because I really wanted to get it without any AT&T branding and, especially, no opening jingle---but I listened to the jingle in the store today and it's so short I think I can cope with that. My biggest disappointment is settling for 32gb instead of 64gb. Truth be told, though, I probably won't fill up the 32gb. But after hanging out here for a while, the desire for the best specs has rubbed off on me.
Anyway, I'm glad to hear that yours is working out well. I'm hoping to have a similar experience.