For me I'm pretty loose as far as criteria goes. If the machine adds something to our sewing machines or does something others don't do, or it interests me, or makes me curious, I'll go for it. For instance the Featherweights don't do anything other better SS machines do, and they don't interest me at all. But I got one for my wife cos she's wanted one all her life. And she hasn't used it since she got it.
I have one of those Kenmores. Mine is a 120-812 I believe and is brown crinkle and a portable. It is one of the best sewing machines I have. Runs quiet, smooth, makes good stitches and isn't finicky at all.
I'd rate it as the equal of many Singers, and better than many others of it's time.
I thought these were made by White as they use the same bobbin as many White machines do.
Joe