Polo wraps don't really offer much protection in the form of support. They do offer protection from scratches and a little bit of brushing from other legs. I have heard that they can help with circulation during the winter months, but I don't know how much proof there is to that.
I really dn't like them for hacking because burrs and things tend to get stuck in the fabric. Not to mention if you have to cross any water polos are terrible for that.
I like the teknas already posted or woof brushing boots which also have different colours :)