It's not perfect, but it's close. The game itself runs perfectly, but as Wichu stated it comes down to how beefy your PC is. If you run the game with LLE audio then you have no audio problems to worry about, but only if you can maintain a stable 30 FPS. If you run HLE, it's a bit more forgiving, but you need a patched Dolphin client to fix some problems with HLE itself.
Aside from that, you can set the graphics settings to whatever your CPU can handle. I've gone close to 40 hours now without a single crash or glitch.
As an added bonus, Dolphin lets you use save states (still save your game normally though) so as soon as I start up the emulator I can just hit F1 and skip all of the Nintendo BIOS, loading screen and loading the save game stuff and just be right back where I left off
Edit: An example of how resource intensive it is. I have the following:
AMD Phenom II Black OC'd to 3.7 ghz
16 GB DDR3 ram
Geforce GTX 670
64 GB SSD HDD
And I can only play this game at 2.5x internal resolution with AA off and anti at 4x with a stable framerate throughout the game (cut scenes included). It tends to dip a bit down to about 24 FPS in combat, but otherwise stays at 30 FPS. The screenshots I took earlier, my PC can't run that at any higher than 18 FPS just running around.
So, yeah, CPU is your bottleneck here. That's the downside to most emulators - much more intensive on resources than running it naively. Still looks better than running it on the wii, though, even without everything cranked