I am a longtime Mac user. I use UE4 on both my MacBook Pro and on my Mac Pro (the small black tower). Epic Games has been working with Unreal Engine (of one version or another) on Windows since 1998. UE4 has been available on Mac since 2014 (I don’t know when they actually started working on Mac support). It is helpful to remember the difference in time that the Engine has been running on each platform when you evaluate them on each platform. Linux is still not available through the launcher, so it is some years behind the Mac in support.
I find that UE4 runs somewhat slower on Mac than on equivalent Windows hardware, and with slightly more bugs. I have also noticed that each major release noticeably brings the performance and behavior closer to that of Windows. A year and a half ago I kept thinking “maybe I should switch to windows…”. Now I rarely notice a difference except in raw performance. Almost all the bugs that I deal with now affect all platforms.
In my experience, you want the biggest, nicest display you can afford for development, but you should pick a lower resolution to run your game in most of the time. Just like in Windows, you can choose what resolution you play your packaged game at, and with what type of fullscreen mode. Most of the time you will just test your game in a small window when you play from the editor.
I feel that comment is childish and hostile. Please keep your comments respectful and accurate. There are many people, including myself, that use UE4 on the Mac every day. If you don’t have any experience with a Mac, then I would encourage you to get some. People can and will succeed with many different tools, even if you don’t use them or don’t like them.
It sounds like you got some bad hardware that can’t handle its own heat. I sympathize. I have had many PC setups that had weird hardware problems that no one else had or could explain. Macs tend to be much more consistent quality with their hardware, though even with Macs you can occasionally get a lemon. Having worked in large organizations with many Macs and many PC’s, I’ve seen the difference in the percentages of hardware that goes bad.
Yes, you can make Marketplace content on a Mac just as you would on Windows. If you do end up getting a Mac, I would encourage you to still test on as many platforms as you can. I bought a copy of VMware Fusion and run Windows 10 in a VM so I can make sure my projects work on Windows (and so I can package them on Windows). That really goes for all platforms you want to target. If you can afford it, get actual hardware for each platform you want to deploy to. You end up owning lots of phones, tablets, computers, consoles, and other devices if you make lots of cross-platform stuff.
The engine handles all the cross-platform functionality it possibly can. Under normal circumstances, the C++ code you write for your game will work the same everywhere as long as you follow Epic’s coding guidelines. The IDE (code editor) you use will be different (Visual Studio on Windows, Xcode on Mac), but the code itself should be the same.