Do you take account of G.INP?
I certainly do
. DS Channel1 DS Channel0 US Channel1 US Channel0
Speed (kbps): 0 80000 0 19999
SRA Previous Speed: 0 0 0 0
Previous Speed: 0 0 0 0
Reed-Solomon EC: 0 140398 0 35802
CRC Errors: 165 165 8456 8456
Header Errors: 0 0 0 0
Interleave (ms): 3.00 0.00 0.00 0.00
That's a Cisco 887VA-M which supports G.INP. With a firmware update it will also support vectoring. Sites not running Ciscos run Draytek 2860 and 2760 routers which also support G.INP with the latest firmware.
The Cisco is fullly tested and certified by BT for use on their GEA-FTTC service without an Openreach modem. The Draytek 2860 was listed as due for testing by BT as far back as April 2015 with no target entry date set. It hadn't passed testing by September 2015. I'm not sure what the current staus is. All I know is that the 2760s and 2860s I use work well. Juniper and Fritzbox models were also listed as due for testing.
The Zyxel VMG8324 and VMG8924 have passed the BT modem compatibility testing and the VMG8324 seems to offer better performance than the HG612 Openreach modem [Source]
The Huawei HG633 is also an approved device as is the Cisco C897VA and variants.
Conditionally approved devices are; Technicolor 589v3, TG598VAC and the Zyxel VMG1312.