Being that XCR users get 0 bonus means that I will wait until something close to the last few hours (or days) to invest - makes most sense as it allows me to gather more information regarding how badly my stake will be diluted. Game Theory and all that jazz.
Share dilution doesn't matter in this ICO. It took me a long time to realize this. Dilution only happens when more people show up with more money that only makes Lisk more valuable. BTC or XCR, doesn't matter. Inflow of either increases the price of the fewer Lisk you now hold. Your donation still has the same overall value as when you made it. There is no reason to wait. If you are going to donate to Lisk, just do it!