Sure, if the enemy Heimer sits on his thumbs and does nothing while you attack his turrets. Of course your autos do more, but you'll take turret damage while you try to kill it, you'll take Heimer auto damage, and he has two other skills to throw at you. The Heimer would have to be really bad to allow you to do all of this.

I personally don't play jungle, but in my general experience, I think both are equally viable. Jungle Jax can gank really really easily since he has lock-on gap closer with leap. I have a hard time choosing which one is "better" because Jax succeeds in both roles.

Thank you! That means a lot coming from you, I actually use your "Karthus Guide" every time I make a guide!