Is < 0 faster than == -1?

If checking some kind of return value, isn't the first one faster since some flag will be set already so you don't have to do an extra comparison?

>>3
mov doesn't touch eflags, rtfm

>>4
Flags Affected
None.
FFFFUUUUUUUUUU----

Flags Affected: n - - - - - z -
                n Set if most significant bit of loaded value is set; else cleared.
                z Set if value loaded is zero; else cleared.
At least on the 6502 it does ;_;