Hair will always take longer than the skin tone, I guess that is down to the transparency but I am sure someone will correct me if I am wrong. I have used BagginsBill's hair shader on a number of different hairs from different vendors and, as you would expect, it works well. That said it is complex and it is certainly not going to help you to speed up a render.

 

 

I use Poser 13 on Windows 11 - For Scene set up I use a Geekcom A5 -  Ryzen 9 5900HX, with 64 gig ram and 3 TB  storage, mini PC with final rendering done on normal sized desktop using an AMD Ryzen Threadipper 1950X CPU, Corsair Hydro H100i CPU cooler, 3XS EVGA GTX 1080i SC with 11g Ram, 4 X 16gig Corsair DDR4 Ram and a Corsair RM 100 PSU .   The desktop is in a remote location with rendering done via Queue Manager which gives me a clearer desktop and quieter computer room.