Yes, according to my sources, there were only 67 functional Ta152's (and that's combined for the C, H0 and H1 models) compared to say, the N1K2Js 400. Not to mention the plane was not well received in a losing Germany. In fact the H model was grounded before the end of the war. (The C model is not that far away from a Dora and was, in fact, a slight development of the Dora.)