Hmm...
"Built like a tank, they seem to last forever. However, I believe they were a bit lacking in the feature department."
That may have been true in the '50s and the early '60s, but by the time of the New Generation models of the mid-'60s, they had much better features. The TOL 906s were so chock-full of features and so pre-programmed, the only machines I know of that could match them were contemporary Lady Kenmores (it must be said that the LKs offered more flexibility; 906s were set up so that you couldn't modify any of their preset cycles).
Later, in the '70s, Maytag extended features even deeper into the line. I have an LA108 from the latter half of the decade; it's a one-speed model that was nearly the bottom of the line. Yet- courtesy of Maytag's almost unbelievably simple engineering- it has three cycles (Regular, Permanent Press, and Delicate), four water temp selections (Cold/Cold, Warm/Cold, Hot/Cold, and Warm/Warm), as well as three water level selections (Small, Medium and Large). In addition, it has a bleach dispenser and a softener dispenser. This is a one-speed machine, so the Delicate cycle is Fabric-Matic, meaning that the machine agitates a bit, stops a while, then agitates a bit more, then stops, etc.
All of this is done with some of the simplest, most elegant technology I've ever seen. It is absolutely all the washer I need. Other brands produced in the same time frame didn't have this many features, because their engineering was too elaborate. For instance, softener dispensers were often solenoid-controlled on other makes, instead of the Maytag's simple reliance on centrifugal force. That meant that such dispensers were too expensive to put on every model. Maytag could afford to give one of theirs with most every machine.
In their time, Speed Queens were supposed to be exceptionally robust machines; they were promoted as such and people who bought them believed that to be true. But from what I can see (and I am willing to be corrected on this point), the survival rate on vintage 'Tags is higher than that for SQ's from the same time frame.
Can you tell I loves me some Maytags? ;-)