The exact sync figure of 32400 is 1 of the banding figures OpenReach use. That and the SNR Margin being as high as it is (the target is 6) points to the line being banded.
Banding usually syncs at an exact figure like 54,000, or 53,999.
It should remove itself. We see quite often that it gets stuck in that state. If it doesn't remove itself then it would require an OpenReach engineer to perform a DLM reset to remove it.
Do you know how long the line has been syncing at that figure? Have you had any burst of Error Seconds on the line recently, any faults, or any time where you have resynced a large number of times in a short period of time? These can all cause the banding to be placed.
This page lists some of the banding levels, though I've seen lines banded at other figures too. Your line looks like it's on the 16.2 - 32.4Mb profile.
Regarding the original question, I own both a Zyxel VMG8924-B10A and a Zyxel VMG1312-B10A. Both devices use the BCM63168 chipset, which is best on my line.
The Zyxel VMG1312-B10A syncs slightly higher on both upstream/downstream on my line and is usually considerably cheaper than the VMG8x24-B10A.
My 8924 has extremely low upstream power compared to the 1312, knocking upto 1Mb off my upstream.