Dapuma, the thing about Mage Wars is that you have limited resources. If you play two pieces of equipment, and your opponent Dissolves both of them... I don't know about you, but I would probably stop playing equipment at that point, and run out my Enchantments or more creatures. And then your other 4 Dissolves sit in your spellbook just taking up space, and (unless you're a Water Wizard) costing you 8 spell points.
Additionally, if you DO end up playing the guy who plays 7 different pieces of equipment, you can put a Dissolve on a Mage Wand, protect your wand with some Reverse Magic or Nullify, and go to town on the guy.