If your evods are cracking, leaking and discoloring you could have an acidic or corrosive liquid. the evod tip is really tough but is not so tough with corrosives. The DBox has a removable drip tip and is basically an evod but it is made of the same plastic, the tip wouldn't break but the rest of it might if the cause is your liquid.
Maybe go with glass like the protank mini II
Just as an FYI: I've had 2 EVODs crack at the clear tip part, but only after several months of use. If you look closely at the construction, you will see that there is a very small part of the tip, where the metal tube ends inside the tip, that has thin walls. It's not a big deal since nothing is made to last forever, and I get a lot of use out of them before I have to replace them.