I would not just quit. Having said that, I recently quit my last job. LOL.
But, there was a difference. I was only there for 2 years and about 2 months. And they were going through some tough times and offered any employee who wished to "separate" from the company, a package which I felt was quite lucrative. For me, the severance/separation offer was 3 months of pay including all medical benefits, bonus program eligibility which would net me about $11K after taxes. I also had 240 hours of vacation I was able to cash out on (I know, I'd be eligible for that either way, just saying).
I live in an area (Orange County, CA) with a lot of jobs in my space (online marketing) and so I felt the gamble was worth it. I found a new job within 6 weeks of leaving the old one.
So to you I'd say, keep your job, but, if there is an opportunity to volunteer for being part of a RIF plan, and the package is a good one, and you live in an area and have the type of profession that is readily available, then do it. It's a numbers game.