19mm versus 21mm lug nuts?

[Enologuy]

I am replacing my stock lug nuts once my new Apex wheels arrive. Are there any pros and cons to using 19mm instead of 21mm?

 

[Watts_Up]

As long as your nuts can handle the 129 lb. ft (175 Nm) torque, maybe 19mm would be fine.
But why do you want to use 19mm instead of 21mm?
Maybe you already a set of nice looking ones, or you want to save some weight...

 

[Enologuy]

I am looking at the Bonoss locking lug nuts and they are offered in 19mm and 21mm. OEM is 21mm so I am wondering why two sizes are being offered. Is there an advantage to either. Why would a company offer two different sizes?