Seldom do I use the TA maps here in UK. I tried the latest yesterday and in an area of just a few square miles of a familiar area TA got the speed limits wrong on no less than three seperate roads. Very disappointing, I dont get this with here maps.
I will say one thing in favour of TA though, about a year ago I reported an error to them whereby a certain road was no longer accessable because concrete bollards had been placed across it. They corrected this error in their next release. I reported the same error to HERE maps but the same error still remains on their maps even today