The following is customers' feedback. Customers are provided with products of 2SC1971, 2SC1972, 2SC2539 and 2SC3022. They have used Mitsubishi products before, which stop manufacturing now. So they ask HG to provide products to test.
Following is the feedback of their equipments test.
1) 2SC1971 - performance is absolutely the same as Mitsubishi 2SC1971 2) 2SC1972 - performance is similar to Mitsubishi 2SC1972, Gp is a little higher than Mitsubishi product 3) 2SC2539 - same as Mitsubishi product. 4) 2SC3022 - without any difference with Mitsubishi product.
Following is original feedback from customer in Chinese.