Since you haven't said much about the companies themselves this is about early vs late. One potential way of looking at this is thinking about the development

Since you haven't said much about the companies themselves this is about early vs late. One potential way of looking at this is thinking about the development of option #1 into something similar to #2 in some period of time. What do you think the chances of that happening are? How long would it take if it did? Is there relatively costless "fail early" mechanism built in to the company at the moment? Would company #1 with the size & funding of option #2 be better? worse? equivalent? How much better off would you be if you arrived at option #2 via option one? (stock, salary, position) If, for example, co #1's current path seems to be, "Spend the next 12 months building then raise more money," and after that it's similar to option #1, you might be able to compare them a little easier. 12 months cost for whatever the difference in stock. Obviously this doesn't take into account anything about the likelihood of the companies' success. That's probably more important, but you gave very little information about that.