HI
So Big dogs come out of the hustler factory, just red and a bit cheaper. Personally I never saw any of the failures that avb has mentioned, though i left the mower game full time 5 years ago. With either one you have a more or less bulletproof deck, will go for basically ever.
Serviceable hydro's are a thing of the past, unless you are a mowing contractor using it all day, every day it is never a problem.
So Rover aren't made by Husky. Rover are MTD/cub cadet (used to be also sold as troy bilt/massey ferguson as well). Pressed tin deck and frame, alloy spindles, Chinese honda copy motor. These are for the small house yard with a lawn, not aussie grass, rocks and sticks. If you jump on a hustler for a demo, then jump on one of these you will instantly feel the difference.
Husky are the old blue dixon mowers. I dont have any experience with the new ones, the old ones were a nightmare.
Also worth considering is the Cox/Greenfield zero turns, Again I dont have much experience with them, But they are aussie built, Fabricated decks and frame.