For me Ogilvy, ACavallo, Ecogold, ThinLine, EquiFit and Kentucky have the best half pads.
i have an ogilvy and a thinline. one of my horses did not respond well to the ogilvy while the other loves it. i use the thinline for my eq horse and it's super supportive. when i would get on with the ogilvy, he would sink back. with the thinline, he doesn't at all.
Amicell it's only $50 and Dover has it. I love mine
ogilvy is my favvv, a lot of ppl say the memory foam does nothing bc it "deflates" but i have the 1' and it does wonders w my horse who has a terrible back. i also have the gummy half pad, which is amazing too, however these are both more expensive options.
thinline is a good brand, and their most basic pad is rather inexpensive. . .i definitely recommend looking into those & seeing if they will do good for your horse.
Ogivly is my favorite I also have thin line but it's not as supportive
Kavallerie is my personal favorite, I have one for my horse and he seems to really like it. Oglivy memory foam pads can squash down and then it doesn't do much of anything- gel is better IMO. ACavallo is also really nice.
Ogilivy is definitely worth the money!
Anything with soft sheepskin is always great. Fleeceworks makes an affordable halfpad that is also great quality. Just make sure you wash it with the correct detergent or you will ruin it