I've bought the Asus router to replace my BT Home Hub 4, which had a limited range and the 5GHz range was very poor (which is ridiculous when 5GHz should have a further range).
Setup with BT Infinity was very easy, although the automatic detection didn't work so well. However, choosing PPoE and copying the username from the HH4 allowed me to connect straightaway. After a firmware upgrade to the latest version, I was then ready to go.
Connecting all the wireless devices was very easy, using WPS to connect, and setting up Wireless Security was also very straightforward. The main webpage for all the menu's and information is well set out, and you have quick and easy access to all the configuration you should ever need. The only thing that I do miss though, is a status page showing the connection to the WAN, which I had on the HH4 (there is an up time on the Asus, but little else).
Wireless connection is excellent to all area's of the house, especially to those devices that can either connect to 5Ghz range or are capable of dual band connection. For instance, in my son's room that is at the opposite end of the house (in a modern 3 bed detached), he still get's 104Mbps connection, which is faster than my broadband connects at. He previously complained about connection issues when gaming, but there are no drop out's and no lag (or no lag from my end, as his ping is always low). I've had no issues with any device not connecting to the Asus, from iphone's to Nexus 4\7, wireless printer (Canon) etc. So compatibility appears to be very good.