I have three S910Es, all genuine-original. One is obviously used and has a mildly kinked cantilever tube. The other two turn out to be NOS Astatic-packaged. They're all diasas. I'm playing one of the "Astatics" at 1.35g in a 5000LAC body which has that in-between inductance of ~270mH (slightly high for 4000D, slightly low for later 66 clones), and it sounds like an S912E-- flat response; strong but not prominent bass; clean, extended top end without harshness; notably good soundstage.