It's solid and an interesting tool in the hands of slower decks.
XX for counters is a bit inefficient though, you pay double the CMC if they only have one permanent that must be destroyed.
Explosion Zone doesn't force you to play bad magic but rather allows you to destroy that one permanent that MUST be destroyed. It's giving you an out on a mana producing land that etb's untapped. The floor is so high that when you do get to use it, it should feel almost like a bonus. Cards like this also commonly force your opponent to play differently which is a nice boon.