An Android phone with a pure Google Android experience or very close to it is really the best smartphone experience. Sadly, this is a relatively small percentage of the smartphones available.
And no, rooting and adding a custom ROM doesn't really cut it. Even the world's most popular ROM (cyanogenmod) is still stuck on Android 4.3 Jellybean with 4.4 stuck in perpetual testing land even though it's over a year old and 5.0 has been released.
There's no indication on any of those pages that you should look somewhere else.
The "snapshot" builds is when you finally start to see something modern. And snapshot usually implies 'alpha' quality... one step up from nightly, but definitely NOT something you want to be running on your real, everyday mobile device. Indeed, from the posts on the forum, it seems snapshot isn't stable. M11 had bluetooth issues, you should revert to M9. M12 has GPS and battery drain issues. Etc. I wouldn't really call that 'stable'.
Also note that this is when clicking the "Download" link right across the top on the Cyanogenmod site, which just dumps you into the kind of confusing download structure where you're supposed to understand your phone's code name (of course 'jftle' means Samsung Galaxy S4, that makes sense) and that snapshot actually means stable. They used to have a far more navigable website where you could easily see the level of support offered for your phone (stable vs milestone vs nightly) before you decided to start hacking it.
They now want you to use the CM installer which is under the "getting started" link on the main page. But the Download link should really point to a proper download page that explains things for first time visitors, not dump you off on the advanced users page with no prompting. Really not a user-friendly setup. And that's speaking as someone that used CM on my last two phones (the original G1 and the T-Mobile G2/HTC Desire Z) but never saw it work smoothly.
nexus 5 still is a really good device, with stock android and it's sold with no contract.
moto x 2014 and moto g 2014 are also really really good devices, with almost stock android (motorola added only a couple of stuff to them -- so little that moto x already has jellybean) and are not that expensive (the official motorola store has the new moto g for $180).
If I want to buy a stock Android device, I'm close to Apple's device range (exaggeratively spoken). Also, I no longer have the time and nerves to Jailbreak or Root my device and install custom Roms, and if I pay up to 700$ for a devices it should work and get me at least 2 years worth of updates.
Not everything is bad though. Apple is working on their device portfolio and the Android update policy has significantly improved, since I last used an Android device full-time.
A brand new base Nexus 5 16GB is only $349 direct and unlocked. A far cry from the $649 that the base iPhone 6 16GB costs.
The Nexus 6 is more a competitor to the iPhone 6 Plus (screen size and all) and is priced appropriately. It's $699 for 64GB compared to the iPhone 6 Plus at $849 for 64GB. The base models of each are a bit cheaper as well, $749 for an iPhone 6 Plus 16GB and $649 for a Nexus 6 32GB. As a premium phone, the Nexus 6 is unavailable in the small 16GB size.
Both the Nexus 5 and the Nexus 6 will be getting updates for quite some time. Neither one requires rooting or a custom ROM of any sort.
My big complaint with the Nexus 5 used to be poor battery life but with the improvements in Android L/5.0 I no longer have any trouble getting through the whole day on a single charge. I was planning to upgrade to a Nexus 6 but I really don't want a phone that big so I'm sticking to my trusty Nexus 5 for now.
Yeah. I have two friends with Nexus 5s that really like them. The Motos would be my 'close to stock' choice, really. Solid hardware and software available at multiple price/feature points.
And no, rooting and adding a custom ROM doesn't really cut it. Even the world's most popular ROM (cyanogenmod) is still stuck on Android 4.3 Jellybean with 4.4 stuck in perpetual testing land even though it's over a year old and 5.0 has been released.