A1990 CBR1000, from a 125, are you mad.
Massive difference in weight, massive difference in power, similar braking ability. Very dropsy as far as handling goes, not the easy riding stuff of today you have to bully the 90's bikes around.
And streetfightered, time bomb. Streetfighters come about because the owner has thrown it down the road and fixed it cheap. An old streetfighter unless it has been a deliberate build I wouldn't touch with yours.
It may be harsh but you wanted views, the virago will do you nothing but good.