I haven't shot anything in a studio so I'm not sure how this would effect moire' with studio lighting. Also in previous threads, it was mentioned that the software used for post can effect how apparent moire' is in a given shot.
Here is an example of moire' one of the shots i have:
I was able to fix it in LR with brushing in corrections.
Back to your questions, I feel I still would have wanted the E version if I had purchased the None-E version from the beginning. But I think it should have went the other way around, buy the none-E version first then decide if it produces sharp enough images for a given job.
Now I think MF guys do see moire' but just don't talk/make a big deal about it as it comes with the territory so to speak. With such large sensors, MF pixels are still going to be larger then many DSLR sensors, so the very fine details are going to be rendered differently compared to very densely packed sensors as used in the D800(E)/D7000/D7100 etc... So that may effect things as well. Also, with MF having to stop down further for more DOF, this will lead to some diffraction and does reduce chances of moire'. If you look up what causes moire', it is caused by when very fine detail patterns line up with the bayer filter/pixels of the image sensor and will cause false patterns and/or color due to current CMOS sensor design that Nikon/Canon use. So with MF and the pixels being bigger, more data can be collected at each pixel and less chances of moire'.
I think Fuji's X-Trans sensor design maybe step in the right direction or maybe even Sigma's foveon sensor design, which seems to do very well at lower iso values, will be the "fix" to any moire' issues with digital cameras.
Just my 2 cents of things. If anything I stated is not accurate to what anyone else knows or has seen, let me know. This info is from what I've read and seen personally.