Classic Equine in a great brand. I myself do not personally like them because I feel they are too bulky.
Pro Equine and Iconoclast also are great brands.
But what I go with are the Professional's Choice SMB 3 boots on all four legs, and the ballistic overreach boots on the front legs. Expensive, yes. Worth it, yes.
SMB3 Sports Medicine Boots Value 4-Pack
Professionals Choice Ballistic Overreach Boots
While it is nice and fun, you sure don't HAVE to HAVE all the colors of the rainbow in boots. One pair of good quality boots will last you a very long time. Unless you do multiple-day events in the mud, you usually can just dry brush the boots clean to re-use them again the next day.