Looking at the stats I can see the Kuda, KN, and Vesper all working out good (besides snipers ofc). IMO the Razorback is outclassed by the Kuda, the Vesper will definitely need ext. mags
The thing with the Kuda is that it has a lot more recoil than the Razorback and the Razorback's 6HK range never comes into play even suppressed. So while the Kuda's fire rate makes it decent suppressed up to 18 meters it's not really usable past that while the Razorback suppressed will still do its max damage (4HK) up to 20 meters and its accuracy allows it to be usable past 20 meters.