HF has cheap engines if the machine is worth the expense.
A couple of years ago, I got a 22 HP HF Predator engine for a Kohler Courage engine that created a hole in the block on my zero turn. (The Kohler Courage engine is notorious for that. Google it)
Anyway, I managed to find a coupon to get it for $549 and purchased it. Except if you do the paperwork on it, it's not the bargain that it appears to be.
HF stopped printing the coupons for that engine, as far as I know. It is now at a normal $730 that gets the price up to the "American-branded" engines.
First, the HF engine has only a 90 day warranty, where most B&S engines have at least a year. If you add the extended warranty to the HF engine, the price can be a big turnoff, especially if you listen to the horror stories of getting replacement parts for the HF engine. I no longer consider a Harbor Freight engine cheap, nor a bargain.