I honestly do not see the point of this thread. If you were genuinely interested in which would succeed in a 1v1 fair battle, sure, but you don't seem to be and are just randomly comparing the two.

Jax is amazing 1v1 vs anyone. Unless he's blinded or silenced he can take any champ out (which is why people use cleanse). Pantheon is not as good. His stun has a 20 sec cool down, if I remember correctly, whereas Jax's stun has a 3 second cooldown. Jaxs ult gives him awesome dps without having to get any damage items, Pantheons ult is only useful for teleporting across the map and trying to control the enemy team (badly).

Pantheons stun is like 9 seconds cooldown
Honestly they are practically the same character with each having a niche

Reasons why Pantheon is better

-Instant aoe damage, just run in heart strike, run out - no need to waste 2-3 seconds auto attacking
-Ranged Damage, his spear throw gives him great harassment early game, and is good for last hitting late game without getting too close or if the target is too far
-Teleport Summoner Spell on short CD, honestly youre not going to be hitting many heroes with it unless they were already screwed some way, the biggest benefit in it is the mobility

Jax is getting buffed so it wont matter soon

You're just comparing stats, which means nothing.
Its like the gearscore vs Skill arguement, just because one has better stats, does not make them better. A good Panth will jump in and ruin any remaining enemies with his heartseeker strike (usually at the end of a team fight, when everyone is weak)
A good Jax can tank any Physical DPS until the casters catch up, and get out with hardly a scratch, or push harder with a stun ruining counters. He also hits harder the more he hits, so if he can get into melee range, you are dead unless you run faster or hit harder.

How's Jax at taking damage? If Pantheon is built for burst damage, he's incredibly flimsy.

Jax > Pantheon. That is all.