Edit: my initial research looks to suggest am on a Huawei cab - so we'll see what happens.
There's 2 VDSL2 Vendors (types of VDSL2 cabinets) in use in the UK. They are ECI and Huawei.
Huawei use Broadcom chipset line cards.
ECI use IFTN/Lantiq line cards (Lantiq is now owned by Intel). Draytek use an Intel chipset in the modem.
The issues so far with the 166 appear to be that the DLM is increasing the target noise margin.
This isn't necessarily an issue with Huawei cabinets but could be how the 166 handles all VDSL2 G.INP.
As there's very little G.INP on the ECI cabinets there's no way to tell if these issues would happen on ECI cabinets also.
The lack of error counters makes it impossible to tell how stable the modem actually performs.
With regards to G.Fast there are again 2 Vendors in the UK. They are Huawei and Nokia.
They both appear to use Broadcom chipsets.
There's no way to tell what Vendor your G.Fast is connected to.
As they both appear to be Broadcom it will make much less difference which Vendor is on your cabinet.