x2 on grooving the boggers. From what I've witnessed, that's the only way they'll have lateral stability on the rocks. As for the thornturds, they probably even suck at being a tire swing.
I've had good luck with thornbirds in mud and in the sand but I also had them regrooved for better bite. Other than that I didn't have much use for em.
Boggers are deffinately the way to go or my personal preference is a good ole TSL regrooved.