That is a really good price for that set and I do like CDT Audio woofers and cross-overs (though that particular x-over is one of their better ones) but I don't like their tweeters so if you get that set don't expect much from the tweeter.
Here, check this: Take this driver on sale. Add this driver on sale. Go here and grab a pair of these tweeters (don't forget to buy the corresponding mount you need). Now you just need to add any 3-way cross over (CDT or not) and you've got yourself a great setup all around for only a little more (which would be worth it) than that original "pretty good" set. Or go active and actually save money over that original HD-set.