May I refer you to me previous post? I have real world experience of not just one but eight
Draytek routers on VDSL2. One site has an ECI cabinet. The rest are Huawei. I know you had a bad experience with a Draytek 130 modem but my own experience suggests that's uncommon.
I'm actually onsite tonight at the site with the best sync rates and we have two lines and two routers - a 2760 and a 2860n+. I'll post line stats but it's going to be in 'Womble time' - i.e. nocturnal, caffeinated, and possibly covered in fur
My very strong recommendation would be to try a Draytek without an external modem first and it it all goes pear-shaped, consider an external modem. That avoids unnecessary expense.
The Drayteks are reasonably good business routers. The major thing that does annoy me is that it's not possible to edit a configuration file offline like I can do for Cisco - or even a Watchguard running PPPoE and upload it. This only becomes an issue with more complicated deployments - like one tonight which has multiple VLANs, VPNs and a range of different host and destination-specific firewall rules. Unfortunately the configuration file has become corrupt which means that it's not possible to update the firmware without starting from scratch. That aside, I like the Drayteks in a business deployment. They're rock steady and provide good security options.
One site I inherited currently has a Netgear D7000 router. I have to run this with an external Openreach modem as the VDSL2 sync on it is hopeless. Not only that, it has no configurable firewalling and port forwarding is primitive. It also only supports OpenVPN. It's utterly horrible. With the Drayteks I can easily configure static site-to-site VPNs and mobile user VPN with multifactor authentication.