I really like the bass small oval brush to groom Leroy and Evie. Leroy has hair that's on the thinner side and Evie has lots of hair and it works great for both of them. I got it from Cherrybrook. I haven't tried any others so I cannot say how it compares to others. For the mustache and hairs near the eye area I use a little comb which I don't know the brand off.
Here a link to the bass brush,
BASS Wire Pet Groomers - Cherrybrook