Why not Ursaring

Machamp gets STAB (Same type attack bonus) so he does an additional 20% damage.

In terms of dishing out power Machamp is more ideal because Machamp, unlike Ursaring, receives the 1.2x STAB bonus (Same Type Attack Base). Because Machamp is a fighting type and because the moves are fighting, Machamp receives this additional bonus. Machamp also receives dynamic punch which dishes out more dps throughout a battle (it can be fired off twice as soon due to its 50% charge energy requirement, compared to close combat's 100%)

Machamp is fighting type, thus has STAB. It's attacks are thus stronger by a factor of 1.2.

Hang onto him though. If defense ever becomes important again, it will be helpful to have fighting moves without fighting weaknesses.

Base attack 336?

Less defense stats, no stab and no Dynamic Punch.

Machamp can have stab, but Urasiring's type coverage is better. No supper effective against flying, psychic or fairy pokemons.