I dont think that you would find anything that works as great as your locale WinUAE.
The FPGA is fun because you can use it to so many different plattforms (Amiga, Atari ST, Nintendo etc etc). And it is super easy to use.
It is really simple to change the settings and very quickly jump from 1.3 to 3.1 or what ever your need is.
Our beloved Amiga computers is starting to get really old, even if new accelerators is produced the motherboards is still produced in the early 90īs with many limitations.
The FPGA concept that MiST and FPGAArcade is based on will settle my need of faster and new ways to play with "Amiga" stuff for a long time. The speed you can get from a FPGA is so much faster than the old 68000-68060. Just see what Vampire is capable of.
The Vampire is also FPGA based and rocks the world at the moment. But you are still in need of a working A600 with different addons to fit your needs.
So the answer is NO, MiST is not as fast or stable as WinUAE.
But if you like new hardware that you can run Amiga OS on and will not cost you 1000$, then my personal tought is that FPGA is the only way forward.