Well, I cant tell you how it felt to shoot the NPP straight, since I use it with a combo as well as some oil to cut it before injection.
I would add a combo of 3 or 4 of the following 4 hormones to a shot and then another 1-2mls of sterile oil to cut it:
1/4mL of 200mg/mL NPP (50mg),
1/4mL of 200mg/mL Test prop (50mg)
1/4mL of 200mg/mL Drostanolone Propionate (50mg)
1/4mL of 200mg/mL Tren Acetate (50mg)
The pain really wasnt that bad, since I would cut it with oil in the end.
The main reason why I make such high concentrations is I dont have to filter as much oil to make the same amount of hormone.
Also, it gives me more flexibility when it comes to how many different hormones I want to use at once without injecting too much oil.
If I only want to inject 2 hormones equaling 1/2mL plus some oil, that is much better than injectin gear @ 100mg/mL equaling 2mls of oil.