My grandfather had the blue one before, he didn't own it for very long because he ended up giving it away shortly after he was gifted a green Kenmore 2621 canister. He might've kept it still if it was bagged, but the Kenmore is a much more suited vacuum for his log cabin anyways.
And one time I serviced a friend of mine's black one that belonged to her daughter, it was the TurboPower version. I liked her green Hoover Empower better.