I have handled both. The Bora is a lot lighter and feels very plasticky in comparison.
The Vepr has a last round bolt hold open - not sure the Saiga has. And a release button right next to the trigger so makes reloads that little bit faster.
The Vepr has a self regulating gas system which they say is better than the Saiga.
The Vepr has an ambi safety where the Saiga does not.
The Vepr has been adopted by quite a few NATO forces where the Saiga has not been adopted by any.
Vepr has a traditional "mag straight in" magwell where the Saiga has a "rock and lock" similar to L1A1 or AK etc
And I have quite a few spare mags.................................
