For now, I am running the 2 stock fans @12 for now. Just built it. They are quiet. I did try the fan controller which does work. Have to hook it up to a molex connector which means I had to add a cable that had one which I didn't care for. Just installed a HR-02 Macho and it's fan is quiet too. This is *nothing* like the P180. It really is quiet and well done. Disclaimer: My GPU died over the weekend and have to RMA it. So I am running right now on the on board graphics. If one has a noisy GPU it might not seem so quiet.
I pulled both drive cages. The upper one is similar to the P180. Remove a thumbscrew and it slides right out. FWIW, the lower cage requires flipping it upside down & removing the screws on the bottom. I was surprised to see it had a small metal stabilizer arm as no reviews mentioned it. Popped the front bezel off (easily) and was able to get to those 2 screws. I decided to not use any 3.5" drives. I have a drive dock for those and just used an SSD and 2.5" 500GB, 7,200 RPM spinner from my laptop. I had replaced my laptop drive with an SSD and decided to use it. I used one of the drive rails to mount the spinner (there are 4 holes for mounting SSDs & added the SSD on top of it with a 2.5" mount. I could only screw in one screw on the side (it is just a drive rail after all) but it just sits on the bottom of my case.
Do I know how much the upper drive cage weighs? I really don't know. But I just picked both up and the R4 seems a *tiny* bit heavier than the P180 cage. 27 pounds is too much? I really like that it weighs so much less than the P180.
Thanks for the detailed response. I have a 3.5" and SSD that I use so I was planning on pulling both drive cages as well. What are the "drive rails" that you mount the SSD and 500 GB on? You can also mount an SSD on the back of the motherboard tray but you won't be able to remove it without removing the motherboard first.
The P180 is supposed to be 31 lbs so it shouldn't be too far off. I do think because the R4 is shorter it might be easier to carry etc so it might not feel as heavy.