I think a He 100 is a lot more feasible at the moment without a 3D converter.
I think once the current big project is underway I'll test out the options.
Quite right. The so called "He-100D" was actually a propaganda designation involving a photograph of the twelve preproduction He-113 fighters developed from the He-112 (which entered limited production and was service tested alongside the BF-109 development models in Spain, 30 of the He-112 were built).
The He-113 was effectively Heinkell's competitor to the Fw-190 as a potential successor to the Me-109 but engine manufacture was a serious issue at the time and one of the main reasons Tank's unconventional radial proposal made the grade was that it used a different one to other planes in service (shortage of Daimler-Benz and Junkers motors was an issue which plagued German aircraft manufacture for some time, just about everything used those motors if it wanted good performance).
As for the He-112 that was a competitor with the BF-109B/C models and shared their engine series. It delivered better performance and was well liked by pilots but I guess political reasons killed it. Not so much favouritism for Willi Messerschmitt himself, but his already worldwide reputation by the time the decision was made. And as I mentioned due to engine shortages it was one or the other...and we all know how Hitler loved a captive audience regardless of the facts.
24 were finally sold to Rumania by Heinkell in despair and probably to recover costs and these were used on the Eastern Front. He probably would have sold the He-113 fighters off too if they weren't earmarked for propaganda purposes.
As a footnote, RAF pilots actually started claiming kills for the entirely fictional "He-100D fighter aircraft," one of a few things which must've bemused their superiors once 'Intelligence improved (or made them rather snotty, one or the other).