saddle soap, whatever's cheapest is my favorite brand! It all works the same. Whatever's most expensive is my least favorite, haha. I even use leather furniture wipes sometimes... leather is leather, all works the same.
For fly spray, I use repel-X or bronco. What doesn't work at all are the "natural" flysprays made from marigold. The flies just laugh at you and attack the horse just the same!
Saddle- I love Pessoa, collegiate, and stuben saddles... would NEVER ride in a wintec, I absolutely hate wintec. Personal preference, synthetic leather is just not as nice. Fine if all you want to do is trail ride, but they are not for me.
Grain... pennifield's is good for the branded ones, but I get my grain from a local dealer who grows it himself and cut out the middleman.
Dewormer... They're all basically the same if you read the ingredients, so I generally compare ingredients and then go with the cheapest one with good ingredients.
Favorite fencing is three-board wood or vinyl with an electric wire, but it's expensive so I like coated electric wire for the price. I don't like anything that's not electric, I just don't trust it. Horses respect the electric a lot better, plus it'll often stop cribbers from chewing on the wood.
Barbed wire is completely horrible, I have seen horses with flesh ripped off to the bone from barbed wire... keeping a horse behind barbed wire fencing should be illegal. So many horses are killed by it.
Other favorites...
Ariat boots! Will never wear anything but ariats. Mine are more comfortable than my sneakers, they last forever, and they are classy.
Ovation breeches, very comfy and airy
Charles Ownens and Troxel helmets... just seem to fit my head right!