Just got back from a long trip with another PPRuNer, and the service we got from the ATC units along the way was excellent (apart from Solent, who were very busy and understandably asked us to stay outside their zone).
Radar information service was given when requested (mostly with the warning that cover wasn't too good).
I've never visited my "home" tower but have been to several others, and would make it mandatory for student pilots if I could. Half an hour sitting at the left elbow of a controller at Drayton or Swanwick is quite an education.