The ATP is basically a warmed-over Avro/HS/BAe 748
Besides them trying to market it as a STOL unpaved strips aircraft, I believe one or more incidents at Portsmouth Airport, the Avro 748 was a good aircraft, still flying today.
By comparison the BAe ATP looked, nor performed, anything like it and was a piece of .....
That said, I did do some contract work for one (one aircraft of the type) ATP operator and they remarked that per bum on seat the fuel economy was remarkably good.