Is this Vegeta after his Zarbon Zenkai ? If so, Piccolo would crush Vegeta. It's implied Kamiccolo = 2x Piccolo and Nail said that if Piccolo could be one again ( Kamiccolo ) he could defeat Freeza. Therefore, Piccolo ( Post King Kai training ) > Freeza 1st Form ( 50% ). I have Piccolo at 300,000, that is, exactly 10x stronger than Vegeta.
What do you mean 2nd Zenkai? During the Namek Saga I see Vegeta's Zenkais like
1st Zenkai - After his battle on Earth
2nd Zenkai - After almost being beaten to death by Zarbon
3rd Zenkai - After almost being beaten to death by Reacoome
4th Zenkai - Mortally wounded by Krillin
If you mean after his battle with Zarbon, I give this Piccolo quite handily. After his battle with Reacoome, Vegeta takes it.