The NZXT s340 is incompatible with the H105, but will work with a little tinkering. If you want to run just push you have the take the cable management bar out, then reinstall it after the H105 Radiator is in. Doing so will cause the cable management bar to pushed right up on the radiator, with a slight bend. If you want to run push/pull like I do, then you have to completely remove the cable management bar.
I have my 6600k overclocked to 4.6Ghz stable, and my temps never go above 65c while gaming. My 970 max temps while gaming seem to be 76-77c. The air flow is greatly improves when I added push pull to my H105, and while I could potentially get greater cooling with a different case I love this little guy.