E.g. Poser weight-mapped clothing that is distributed as cr2 solely won't work in DAZ Studio as such, which is quite some clothing amount for Dawn (the rigging of the DAZ Studio Dawn is different than the Poser Dawn). If you want to buy clothing for Dawn, it is best to stick to DAZ Studio supported products only - some vendors support both DAZ Studio and Poser in that regard. There is also some Poser-used rigging type (bone structure etc.) that is not easily transfered to DAZ Studio, which I think one of the Miki characters used, however, this one should be less frequent or almost non existant. Furthermore, while DAZ Studio has become more forgiving at interpreting bad quads or n-gons (polygon faces defined 4 or more points), there are some products which cause errors there, which can result in an odd surface structure or black polygons on the model. The latter is again not that frequent, but yes, I got a 'rosity product which is unusable due to that in DAZ Studio.

Space ships and the like should work for most part, but certainly would require at least tweaking of the surfaces/materials by yourself. If in doubt address the vendor and ask whether it potentially works. You can also always ask on the forum whether it is ok to risk buying a certain product or some product reviews may mention whether it works in DAZ Studio or not.