Dimensions aren't radically different, with the Moto G5 Plus coming in at 2-percent shorter, 1-percent narrower and 87-percent thicker.
Keep in mind, though, that the Moto Z's razor-thin depth measurement includes the phone only without any of its modular backplates attached. Also note that the G5 Plus has a curved back, and its depth measures only the thickest point.
Without any mods attached to the Moto Z, the G5 Plus comes out 14-percent heavier.
Motorola took a step in the premium-build direction this year, as the Moto G5 Plus steps away from its all-plastic predecessors with some aluminum onboard.
You have two or three color options for each phone, though the Moto Z can get a different look and color depending on which mod(s) you snap onto its back.
Speaking of which, the Moto Z takes a unique and simple approach to modularity, with built-in magnets that snap various attachments into place on the back of the phone.
Our favorite mod was the simplest: a battery. But there are also options for a camera with optical zoom, a JBL speaker, a projector and a car-mount dock. There are also functionless mods that add a different material or color to the phone.
The Moto G5 Plus' screen is about 11-percent smaller than the Moto Z's.
Being a budget phone, the G5 Plus naturally gets a lower-res (but still sharp) 1080p display, compared to the ultra-sharp QHD screen on the Z.
Motorola went with IPS over AMOLED in its mid-ranged phone.
The G5 Plus has a mid-ranged (but still capable) Snapdragon 625, while the Moto Z uses Android's early-2016 high-end silicon.
Depending which storage tier you choose for the G5 Plus, you get either 2 GB or 4 GB of RAM.
Internal storage options are identical.
Both also have a microSD slot.
Camera resolutions are similar, though we'd be surprised if the mid-ranged G5 Plus' camera were as good as the Z's high-end one.
Camera aperture (rear)
The Moto G5 Plus does, however, have a slightly wider aperture. This can often mean better low-lit photography.
Lenovo left Optical Image Stabilization out of the G5 Plus.
The Moto G5 Plus has a 15-percent bigger (higher-capacity) battery, which, when combined with its lower-resolution screen, could bode well for battery life.
Remember, though, that the Moto Z gives you the option of snapping on a battery mod for a big boost (at cost).
Both have quick-charging tech baked in.
Both have some light water resistance, but neither has a significant IP rating.
Both have fingerprint sensors below their screens.
One compromise in the cheaper Moto G5 Plus is a lack of NFC, which means no Android Pay.
Both run mostly-stock versions of Android Nougat.
The G5 Plus launches this month, while the Z was introduced last (Northern) summer, so it may be due for an update announcement within 3-4 months.
Starting price (full retail)
Motorola keeps pushing the boundaries of how good a $200-300 phone can be, and the Moto G5 Plus looks like it could raise that bar higher. Stay tuned for more in our full review.