Hi, I've been using G750JZ for about a year now, which is in the same line of gaming laptops from Asus as the one you're trying to buy. G750JM with exception of better graphics (880M). Here where I live the newer series, which is G751 (not the newest) has better graphics (970M) better processor ( 4710HQ) and it costs the same, so I would advise you to check the series as they may be priced same or just a bit higher for essentially a great upgrade.
So far I had 0 issues besides the HDD which died and even that I believe it was my fold as I was not really treating it correctly but now I own 2 SSD's anyway and everything is great again. Besides that I had no issues again and I am not the only one. You'll probably see a lot more issues regarding the laptops from Asus here than positive things but that's only because you usually don't comment if you don't have any issues here anyway so that is to be understandable and should not scare you or change you way of mind, not that I would mind if you bought something else, just to clarify.
Now on to the questions and if you have some more feel free to ask and I'll answer the best I can
😉1) I am using my laptop for everything. Gaming, video editing, programming, audio editing, photo editing, you name it I probably did it. I had no issues performing any of the tasks that would affect my experience as far the contrast goes. I do have some screen bleeding but that is due to the quality of LCD panel, which is to be expected but other than that the screen is great.
2) I wouldn't know about the "lap desks" as you named them since I never used one. I am currently a college student and I move a lot for the reasons of getting home and going back to the college. After a while you get used to the weight, I carry mine in a backpack I got with the laptop (Some countries get even headset and mouses but I did not have that option) and it's also quite high quality one. Sorry for not being helpful here but besides telling you that the weight is worth it since it is cooled quite well I have nothing to say here.
3) I wouldn't know about that specific laptop not being compatible with Windows 7 but mine, which is again same line just different laptop (Again, they're essentially all the same besides the graphics), has no problems running Windows 10 and Windows 8.1, which I used before. I never used Windows 7 since I bought laptop without the OS and installed Windows 8.1.
4) I do not think that is true. There is not a single driver on my laptop that had to be installed using "very" specific needs. With Windows 10 everything gets installed automatically anyway and using that I had no issues what so ever. I did had to install the FN function drivers, since that is laptop specific but other than that nothing else I believe. Even the mouse drivers got installed automatically with functions optimized for Windows 10 and what not so really again no problems at all.
5) I cannot answer that as I honestly never used any program regarding what you asked. I usually always do clean install whenever I install new operating system and if I do need some files that are not already backed up on the cloud I put them on my USB and then just copy them back on.
6) If your fans are clean and if the thermal compound is well applied you won't hear them unless you're doing some actual work. Even when you are doing something like editing some videos or like having 20 tabs opened in Chrome at once they are quite silent, active but silent. By fans I should say CPU fan since GPU fan won't turn on at all unless you're using it, which is when you're playing games or using it to render something. As for heavy editing or gaming they do get loud but not really that loud. You can still hear everything just fine and what not so unless you'll be rendering or playing games all the time you should do just fine with the sound
😉7) Well you said you're going to give it SSD(s) that is really the best thing you can do. In my case, my laptop boots in 7 seconds and turns off in the same time and then I can use it for what ever I want to. I would maybe recommend getting a custom thermal compound repasting done as mine and many others (Probably the only bad thing I can say about this laptop and Asus) was pretty horrible. It was smeared all over the graphics card and looked as it was applied by a brush, the CPU one was fine thought.
Other than that I have nothing else to advise you and again if you have some questions feel free to ask and I'll try to be as helpful as I can.
P.S: The temperatures are indeed quite low on these Asus Rog series. When they came out they had the lowest temperature out of all gaming laptop brands, which includes Alienware, MSI, Clevo, Origin and what not. When gaming in really demanding games (Because that is pretty much the only time you'll see high temperatures or when rendering a video) the highest CPU get is about 80°C and GPU about 85°C with expection of some games that are REALLY demanding like The Witcher 3 about 88°C sometimes 90°C. Still with everything in mind it runs cool indeed.
Cheers
Asus Rog G750JZ
Screen: 1920x1080 17.3'
CPU: Intel® Core™ i7-4700HQ (3.4Ghz @ -70mV)
GPU: GeForce GTX 880M 4GB (OC +125Mhz Core, +600Mhz Memory @ 1.062V)
RAM: Samsung 32GB 1600MHz
Storage #1: Samsung Evo 840 250GB
Storage #2: Samsung Evo 850 500GB
Storage #3: Seagate Barracuda 2TB
Storage #4: Samsung Evo 128GB MicroSD