It depends what you plan to do with the case, what components you want to put in it. They each have their drawbacks which would make me look at a different case besides these two. The spec 3 has the issue of being a little narrow so it has trouble supporting many tower style air coolers. Even the budget cm 212 evo is too tall of a cooler by just enough that it doesn't fit. You could either get a lower profile air cooler of some sort or go with an aio water cooler to overcome the limitation. It has good support for longer video cards though (420mm). The cc 830 is a wider case and supports coolers up to 170mm in height which is pretty much most air coolers whether it's the 212 evo, noctua nh-d14/d15, phanteks coolers etc. It appears to have non removable hard drive cages though which limits the length of video cards to 310mm which could be a problem. For instance a gigabyte gtx 970 card is 312mm long. There may be shorter video cards, but depending on which card you have or might want to get in the future a case with this sort of length limit for the gpu could be difficult to work around.