If you want very few issues with a router that does 802.11n, that has a gig port, that performs adequate QoS and bandwidth management, that has an object-based firewall, and that will work with BT infinity as well as ADSL, then pony up the extra for a Draytek Vigor 2820n.
Whatever you do, don't buy Belkin. Dlink are almost as bad.
Netgear and Linksys are not so bad, but both suffer from short lifespans and spurious errors on differing firmware.
I'm in the middle of migrating my clientbase to the Draytek as it's rock-solid compared to the others (and until you have a router which causes you no bother you'll not appreciate what the extra cost buys you).