The functionality has been available on an opt-in basis for a while now, and I can confirm that it massively improves Firefox's performance and responsiveness. Whether it's "as snappy as Chrome" is a separate question; I've never found that browser as responsive as seems to be the general experience, so I can't really speak to the comparison, but I certainly can say that Firefox itself is much more comfortable to use with e10s enabled.

I've found Chrome as buggy and unreliable as it's been fast and responsive. I actually switched to Firefox on my Windows PC because Chrome just stopped rendering properly (not just rendering HTML, the entire window was broken). I also have to turn off users' hardware acceleration at the office so that their 'my tabs go blank!' bugs stop happening.

I get a lot of weird graphical glitches with Chrome on Windows 7, too - something about the way it draws its windows doesn't always play well with DWM, so they'll leave bits of themselves behind when dragged, or flicker weirdly when dragged across display boundaries, or otherwise uniquely misbehave. Even on machines where the display hardware sucks enough to make graphical oddities relatively common, Chrome stands out in the frequency with which they occur.

You might confirm that your video driver is up-to-date.

My experience with e10s enabled has been a very smooth.

If you want to check wheter or not it's active for you, go to: about:support and look at "Multiprocess Windows"