Last but not least is the price and the release date. If you need a new phone now, the Note 4 is the way to go. If you're trying to decide on one vs the other, we'd suggest waiting for the Galaxy Note 5, or until September for when the Moto X Pure Edition will be released. Sadly it's still narly a month and a half away.
However, an important aspect for all buyers is the price, and this is another area the Moto X wins.
The Galaxy Note 4 launched for $799 or more outright from most carriers, and $299 with a new 2-year contract. It recently has lowered in price, but still costs well over $600. One thing that's 100% clear though, is you'll almost be able to buy two Moto X phones for the price of one Galaxy Note 4. Ouch.
The 2015 Moto X Pure Edition with the same size screen, more customization, slightly better specs, a great camera and more, is only $399. That's going to be a problem for most, including Samsung.
That said, $399 only gets you the 16GB model, and most likely $429 will be what they ask for 32GB which should match the Galaxy Note 4. Wood or leather backs are $25, which still puts the Moto X a few hundred dollars less than the Galaxy Note 4 unless you get it on contract.
The Moto X will be an excellent stock Android smartphone full of customization, great performance, a huge screen, and won't break the bank.
There is one problem though. Motorola isn't selling the Moto X through any carriers in the United States. Instead they want nothing to do with carriers, and will sell it from Motorola.com, Best Buy, or Amazon. That means you can't get it on contract for less, or make monthly like most US carriers offer, which is one way users will be able to get a Note 4 for around $26-$30 a month.
If you can't afford $400 outright you'll need to get a Note 4 or 5 on contract, or get a payment plan and essentially a credit card from Motorola.com, as they actually offer financing for those who need it.
Tough choices ahead, that's for sure.