I've had a half-dozen of each. The velocities I've obtained are fairly close, and not enough to make a shooter choose one over the other, frankly.
One peccadillo I HAVE really noticed though, is that every .257 Roberts I've owned (2 Brownings, 2 Rugers, 2 Remingons, 2 Winchesters) were finicky to load for.
Every .250 Savage I've owned (six 99's, a Savage bolt and a Remington bolt) was dead easy to load for.
That said, the fact that I still have two .250-3000's and a .250 Ackley doesn't make me stop wanting another Roberts.
