Earlier quoted context omitted.
> I have yet to hear a single case of an employee purchasing their options when they left and thinking it was the right decision later on. I know at least a dozen ex-colleagues of mine who fit this criteria. When the company in question exited, it created 400 millionaire employees.
that's the problem with anecdotal evidence - you can't really tell for sure a company is going to become a massive unicorn often until very close to the point it does. I've worked at companies that raised many millions of $s and seemed very promising and a few years later went out of business. Who becomes a winner is also not always completely "fair" (as in it depends somewhat on circumstances/fortunate happenstance)…
At the end of the day you're really throwing money into a black box which may turn out to contain a trash can. There is more financial transparency in penny stocks.
I've personally had great success with RSUs, but those are ultimately part of your comp even if you discount them to zero - there is no requirement to put in additional money.