there's sooooo much better stuff out there than infinity for the same/less/slightly more.
I feel like they're the bose of the Aftermarket Audio Bestbuy/circuit city crowd. Yes, you're getting a good product, yes you're paying 4x what you should be. Yes there are much better products out there.
I bet you can find a full set of component speakers for $75 more than what you would pay for those tweeters.
I reccomend hunting down a used pair of Diamond audio hex series components.
I have massive audio ct1a tweeters that i bought for $35.