I don't like crash/rides generally
What the previous poster said is correct, if the cymbal is too heavy, it will not crash well. That being said, those cymbals that are sold as dual purpose (crash and ride) tend to do both poorly. You are much better off getting a ride that you really like and then picking up a good responsive crash cymbal. Buy well and don't waste your money on entry level (ZBT, B8, etc.)
cymbals, they won't ever sound good. Buy one at a time (not packs) and show up at the cymbal room at your local retailer with a pair of your sticks and try out everything and only buy those that really "speak" to you. Even on sale, expect to spend no less than $300 for two really good cymbals.