Ill use chest, inner/outer forearms, deltoids, that's pretty much it after the scrotum. Sometimes it's all scrotum, sometimes it's all other spots and yet still I'll split a dose in those areas. Obviously scrotum is targeted for DHT conversion but otherwise I think that "best levels" is a bit of just chasing your tail, that my experience. Too, my protocol has me using multiple applications through out the day so I do rotate it around. My unique physiology/matabolism with Test and Edstrogen has dictated my methods. To that end...trial and error and lab tests got me here. You'll have to do the same.