I pump pure speed on mine. Always. Nothing better than a Roo with 200+ speed.
These guys are great at gathering thatch. Maybe not as good as a Bronto or a deer, but they are so fun. I use any excuse to take one of mine out to get some thatch.
They make the same bite noise as a parasaur, which is disturbing, but hopping around from tree to tree is undeniably fun.
I find it useful if you pump nothing but weight and then harvest metal with it, just put yourself in the pouch and have a friend walk up to metal nodes, then you can harvest metal without even leaving the pouch!