Yes there is, Typhlosion takes 5 spots and you need Candy, reason enough NOT to play it.
Magmortar's damage capability is mediocre at best when not using acceleration and scramble isn't working. That means you are reliant on your opponent activating your scrambles, meaning your opponent decides when you can go aggro. Gallade will see this, drop a sonic blade, and laugh.
There is NO reason why not to make your deck far more powerful at the cost of only a few spaces, there is no reason not to use Typhlosion.