I can't advise what you should or shouldn't do, other than to educate yourself and make your own decisions.

Personally, the only reason I'd see to invest in the first five day period is if it was transparent that there was a HUGE sum of like a billion dollars already contributed that'd put the price for that period at a relative low.

Otherwise, I'd be watching day-to-day at the very end of the 23h periods as to what price is relative to earlier periods and what the exchange prices are - which would be tough without an app like suggested above or knowledge of how to read the contract coding as it updates...