Ask Raul, he has more arms than a giant squid. Seriously, some like the convenience of having more then one cartridge always available; big mono collection, just like to have different presentations of the music, whatever. My two phono stages can be connected to two turntables[or arms] at once so I can demo more than one table without long hook up period. I once used two arms but ended up using one all the time; but if you like playing with cartridges multiple arms is a great way to go. Yes, you could hear the differences. ALL turntables sound different and the more expensive ones are almost always better. Worth it? Your call.
