There doesnt seem to be much difference between the Zyxel & the HG612 on broadstairs line when it comes to E/Secs.
I agree that the Zyxel may have given some more CRCs but from the graphs I wouldnt say its a substantial amount certainly not to the point where the DLM is going to be interested. SHINE can produce different burst levels and vary too much to drawn anything conclusive for example look how much the 26ths and 27ths varied whilst still using the HG612. On the 23rd broadstairs line suffered quite a steep peak burst of CRCs but in all fairness who is to say that it couldnt have happened on the HG612.
You may feel Im being defensive about the Zyxel, but I do feel its totally unfair to compare it with the ASUS - theyre not in the same league. The ASUS has big problems in that its causing most people to be DLM'd.. yet the Zyxel has given quite a lot of people much better line conditions. I'll admit that Zyxel could perhaps be more pro-active with f/w releases, but look at Ronski's line is an example. He suffers from lots of noise yet the Zyxel gives him a higher bit rate and more recently he even had interleaving completely removed. OK it didnt last for long because he suffered a really nasty noise burst which made the DLM take action again.. but since being on the Zyxel - and hes been on it for several months now, he certainly seems to have faired better when it comes to the DLM and bitrate.
Ive got a couple of TPlinks here. My line gets loads more errors using the TPlink and it wouldnt even give me an 80/20 now, it doesnt perform anywhere as good as the BCMs. TPlink sent me another router just to check it wasnt a one off hardware issue, but both perform the same.. yet I still class it as stable because it performs along the same lines as the ECI modem and better than the HH5 when on a BTr line. Most people seem to find that the BCM routers do perform better, yet there is still the odd line which does better with the Lantiq chipset.
On the whole so far, I'd still rate the HG612, the Billion and the Zyxel in the top 3. Id certainly rate the ASUS as the worst... and all the others fall somewhere in between.
Agreed, although I think the zyxel has some issues, as you said the issues are not even close to the asus which seems a train wreck of a device.
I love my billion, stable fast firmware, and can even now collect stats using the WAN cable so no 2nd cable needed.
The zyxel syncs higher than the billion but on certian lines may have a higher error rate and some of the firmwares are flaky. Also as a router the zyxel is a better spec than the 8800nl.
The hg612 is the cheapest (or even free if openreach gave you one) and remains a solid choice.