It depends what you want.
If you only want the wheels to spin, then 23.46 is okay.
But if something doesn’t work and you need to troubleshoot, or if you want to use almost any modern features or devices, then you’ll probably want to use 5.2 from either VESC Tool or variESC Tool.
Just to clarify (I’m not up on the firmware timeline), sounds like 23.XX is a Unity/Enertion branch and 5.X is the official Vedder branch?
Bingo Trogdor!
If you open the latest version of VESC tool and connect a Unity that’s on the 23.XX Unity firmware, it’ll probably give you a pop up message about the older firmware and limited ability to change settings.
The difference between the Unity firmware and FW5.XX is fairly significant.
And, as has been said, they really aren’t comparable at this point.
Be prepared that it could take several hours, so do it on a wired connection. I don’t remember which specific update is the super slow one. Most of them happen in about a minute.
He is not kidding. Some of the FW updates take FOREVER.
It has something to do with the VESC running out of memory to store the code as it rewrites into itself… Can’t really explain well and can’t remember where I read that or who said it.
I think @xsynatic discovered it first, and I can’t remember which versions. There’s even a way to do the upgrade in 2 steps, a minute each, that avoids a multi-hour update. I think it involves 3.65 as an intermediate step but I don’t remember. But I don’t remember and since you can do the update and wait a couple hours, I don’t think it’s super important to research right now.
what is “app settings” → “general” → “App to use” set to?
I’m going to guess it’s set to UART. and not PPM and UART. or PPM. and this is where the user error lies. it would explain the symptoms you posted.
if you are connected via BLE over UART, definitely set it to PPM and UART or you will drop your connection.
FWIW, most of this should be cleared out of @BuildKitBoards’s thread. it’s likely config issue confusion and nothing to do with Xenith.
One could argue it’s not offtopic as the Unity and Xenith are really the same hardware with some extremely minor differences.
I was thinking vesc_tool confusion isn’t really about the untiy or the xentith. but. i mean there is some connection or it wouldn’t be here.
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yep that’s it for sure
If you are using latest VESC Tool, it should be fine, no need to jump multiple firmwares
Just like the old unity thread 
“the unity threw me at full speed! Wahhh. Oops my motor cable came undone nvm”
U can go on the vesc tool and pair ur vesc with the tool itself so itll auto connect over bluetooth without goin through the selection hassle no need for a metr if u dont want one
Another thing, is this whole duty issue with the xenith on 5.1 is just exclusive to the 5.1 firmware cause i updated both my xeniths to 5.2 but havent ridden them yet since im still building the board but does the issue transfer over or nah?
Do NOT do this unless you write down or save your ESC’s UUID. You’ll need that, like a password, if you ever try to connect from a different computer or phone. Otherwise, you’ll be locked out unless you run a wire to a USB port.
a uuid i dont need that or even heard about that til now
If you pair it, you can’t access it wirelessly from any other device without the UUID. (But you can wired)
If esk8 hacking was to become a thing, this would be an important safeguard. As-of now, I haven’t heard of it ever being a problem.
Getting locked out could be a real problem if you change phones or whatnot.