I'm not sure I'd laud startups for 'career security'. Outside the valley echo-chamber, few companies have any respect for startup experience. ('startup' sounds a lot like 'small company' if you aren't a hacker...)
Also, for every startup where young employees get a chance to punch above their weight, there's another where the devs grind all day long on customer support issues and maintenance.
On the whole I'm personally more inclined toward startups than large companies, but I've been around long enough to be wary of mythologizing them. They have their own set of dysfunctions that can be as stressful as anything you'll find in a bigcorp.
Alternatively, working at a startup may not have the same cache when not in the Valley, but you might get a chance to work with some awesome tools that are ahead of the curve that would get you experience for a future job.
I think it totally depends on what you do there. I'd probably hire someone who has the full gamut of dev, sysadmin and customer interaction experience from a startup. Less so if they couldn't effectively describe how they'd helped get the business running.
> working at a startup might not have the same cache ...
I've co-founded companies in Boston, NYC and SF and I've also worked at large software companies. I've seen quite a bit of appreciation of startup talent in all cases.
Also, for every startup where young employees get a chance to punch above their weight, there's another where the devs grind all day long on customer support issues and maintenance.
On the whole I'm personally more inclined toward startups than large companies, but I've been around long enough to be wary of mythologizing them. They have their own set of dysfunctions that can be as stressful as anything you'll find in a bigcorp.