I went from SD TV to uverse HD, so my case may be a study of ignorance being bliss. I have not benchmarked it against other options.
How do you define "robust"? I am a fairly casual internet user, for lack of a better term. I do not do a lot of downloading or online gaming, so it is fine for my needs. I stream netflix on my PS3 through the wireless network and have no complaints.
The only time I have ever had connectivity problems was when my yellow lab dug up the cable running to my house and chewed it in half. But that is a whole other story...