They are pretty good actually, good work with them and let's hope we will see some more good ones =)

Your having some strange anatomical issues here. The business guys' legs(the thighs really) are pretty damn skinny when compared to his upper body, as he might be suffering from polio.

The ninja fellow looks kinda wierd. I guess I'm not a fan of the current design you got here. His muscles seem a little awkard.

• His nipple( if that dark spot is a nipple) seems crooked, or ill-placed
• His forearms are kinda longer than he upper arm
• the bandage on his feet look a little sloppy right now. Maybe try to lighten the darker lines where the light is shining on it.
• and sorry to say this, but that pose kinda looks funky. Not very ninja-ish( or any type of martial arts) if you ask me.

But keep in mind, this is still a good rendition of a kof style, considering it your first since ussually drawing in a cartoony style. With a little more practice and anatomy study, you'll get it down. Good job anyhow...