How does the stock thing work? Is it given to all engineers? It seems to be just Silicon Valley companies who give away stock/options as a matter of course, so I'm a little mystified.
If this doesn't sound questionable enough, keep in mind that this is the only retirement plan they offer to employees and that upon leaving the company employees are required to sell back their shares.
Maybe it's totally legit, but it always struck me as very, very questionable.