Its usual (at least for me) for the initial load up to be slow, while it complies shaders. Its also normal for the first time in a session when you open/edit a file like Primalgamedata for it to take a bit of time.
If its slow EVERY time you try and open/edit primalgamedata in a session then i think your comp may be struggling, thats not to say you wont still be able to use it - it purely depends on your patience 
And btw, i just upgraded from 8GB RAM to 16GB and noticed on difference in the speed of using the Dev Kit. Probably the best upgrade you could make (price per performance) would be an SSD, but i think it would have to be 100GB/120GB minimum depending on what you plan on createing