switch firmware

I just picked back up on my project of switching my amcrest firmware to either dahua or a different brand that is equivalent to. IP4M-1028B V2.420.AC01.3.R 06/02/2018 IPC-HX1X3X-LEXUS_Eng_N_AMCREST_V2.420.AC01.3.R.20180206 I know Dahua does not make too many PTZ 4MP camera however I found...