If you limit your potential losses on random rollers by not betting on them or by using the 5-Count on them reducing the number of random rolls you bet on by about 57 percent and you bet only one bet on them at table minimum here we go:

Say I go up on three numbers. A Pass line and two Comes with full odds. That is all I can lose (one, two or three bets) if I immediately seven out. However, I can win much, much more on long rolls. I can also win on repeating numbers --- even just a few of them. So losses are contained (bets on random rollers are negligible). I'd say a 300 dice controller would be a winning dice controller.