I take 476 from rt. 22 south to I-95 once or twice a week. There's a stretch of construction, maybe 10 miles. Once you get down towards rt 3 and rt1 there can be some backups. Overall, though, it's not a bad route.
On the northern end it is the NE Extension ( Toll Road )... below the Pa Turnpike it is just the Blue Route with no tolls.. It is a main artery to 95, so it can get congested depending on the time of day.
Overall it is a decent road, with decent flow most of the time. We take it when we are heading south and do not want to deal with 95 in Philly..
Once you get on up near Allentown, you will hit some on going construction down after the Quakertown or Lansdale exits, but that will clear up.
Always crowded, always aggressive drivers, always high speed, always lot of construction, seems you always hit a backup, a lot of up and down hills and for an interstate it is pretty narrow and to think you have to pay for all that when you drive it.. Other than that it will get you headed to Del and it is probably the best way to Del. from that part of the world..