Yep, Nathan's a Good Guy:
Nathan (Electrolux-Dude) has sold me three machines - two Luxes and my TriStar. All three experiences have been more than satisfactory.
Nathan is right about TriStar motors often suffering from dirt and needing a cleaning; on all of the machines he's sold me, he has gone through the motors and put things right. You know how bad most people are about taking care of vacuums! If you want to have a trouble-free TriStar, it is essential to keep up with the filtering system, to keep dirt out of your motor. TriStars have a quadruple filtration system, and three of the four filters affect the motor.
The first filter is the cloth bag. TriStar's instruction manual says you can use the cloth bag by itself, without the next filter, which is a paper bag that fits inside the cloth one. I personally do not recommend that practise; paper bags are a lot cheaper than motors.
The third filter is a motor filter that fits over the motor housing. It is plastic, with a foam filtering element. It is washable, so keeping it clean is easy.
The fourth filter is an afterfilter than fits over the exhaust. There are two different afterfilters available - the standard one, which is just a little foam element inside a plastic cap, or the Filter-Fresh afterfilter, which is a huge, mushroom-shaped filter that replaces the standard afterfilter. I personally use the standard afterfilter; the standard filtration system is so good with the paper bag in place that I have never found the need to use a Filter-Fresh. But then, I don't have any serious allergies. When I vacuum with the TriStar, I don't see any dust again for a day or two. With a Lux, dust is visible again within a couple-three hours.
Nathan ships promptly, and he stands behind his work, so I do recommend him.