Yes, it does matter. If the stock has appreciated in value, your exercise price may be low but your AMT bill may be high even if you have no liquidity at all.

Yes, it does matter. If the stock has appreciated in value, your exercise price may be low but your AMT bill may be high even if you have no liquidity at all. In my case I paid more in AMT than I did to exercise all my shares, though both individually were large and incredibly risky investments. I could afford the risk and it did eventually work out for me, but some people can't afford the risk or frankly don't want to deal with the incredible complication of doing it. Just trying to figure out what your AMT bill might be involves doing your entire tax return based on projections, which depending on what time of year you are leaving could introduce quite a bit of inaccuracy and guesswork. If you have an extended exercise window you just don't have to worry about it. If you want to take the risk of early exercise to get better tax treatment, do it. But if you don't (which I suspect will be the majority of people), all of the complication goes away completely... just sit on your options and exercise-and-sell when/if you get a chance at liquidity.