Blaziken vs Heracross

Probably not too many that have decent ones of both, I have an ok 2075 Heracross that I use somewhat often. Also a newish 100% level 25 fighting Blaziken, when I get it to 30 it'll probably stay on my radar. What never leaves my radar are my three 1950 to 2175 FB Gengars, the computer recommends those very often...things I never planned to have, but those were the easiest tier 3s for me to beat in July/August...that got me a lot of candy, then Halloween, now weather boosts. I think they do ok considering revives aren't scarce, but potions are pretty slow rolling in--just takes a few small ones, also I don't flinch too bad when they are on the bench--no threat I'll hastily give it a hyper potion

Heracross is better.

For base stats, Blaziken's attack is 2.6% higher than Heracross, but Hera's tankiness (defense*stamina) is 34% higher than Blaziken's. So stats-wise Hera is better (in fact Hera is marginally better than Machamp in base stats, but Dynamic Punch makes Machamp shine).

You specifically mentioned the use as a fighter gym sweeper, so the charge move matters a lot. Both have one bar charge move and FB is usually an overkill especially for demotivated gyms, so it's not really that efficient. FB's cast time is also a lot longer than CC, which is not good considering Blaziken is more of a glass cannon.

The only advantage Blaziken has I can think of is that it takes neutral damage from Fairy moves such as Blissey's DG. But note it also adds the weakness to ground and water moves from some common defenders like Rhydon, Gyarados and Vaporeon.

Hariyama is a much better gym sweeper than these two - easy to get especially when you take advantage of weather bonuses, and having access to Dynamic Punch which suits better for all purposes. Besides, it has the bulk.

What is Heracross?