moloss,
I'm no livestock trailer expert, but I'll 2nd Paul's Eby recommendation. A friend of ours has an 8-horse Eby horse trailer. It has taken some serious use and sometimes abuse and has held up remarkably well over the years. Other than normal axle/wheel bearing/tire maintenance they are easy to take care of. Just remember to hose it out after every trip else the urine will eat metal like you can't believe.
Of course here in the north aluminum is king due to road salt. Perhaps in the heart of Dixie you don't have those problems
.
Having recently bought a new gooseneck horse trailer, we found that the price premium for all aluminum was not bad at all.
Look for full tube upgright posts and not just C-channels. American made axles would be on my requirement list. LED lighting is nice.
~Paul