Good third party routers are Asus, Billion, DrayTek, FritzBox and TP-Link.
The model you decide on will depend on your requirements and budget. DrayTek and FritzBox are the most expensive, you won't get a Fritz sub £120 and DrayTek are even more expensive. TP-Link had some issues with IPv6 earlier and have had almost a year to sort it out, so check before buying. The others all have full IPv6 support out of the box. Whatever you decide on get one that supports VDSL.
Avoid Netgear and Linksys if you want IPv6, they don't support it properly.