Crystal value to choose for fuse calculator

I just discovered this useful fuse calculator.

http://www.engbedded.com/fusecalc

I am using an external 8Mhz crystal. When I wanted to pick the right fuse value for the external 8Mhz crystal, I see many choices for different start-up time. May I know how to choose the right start-up time? Is it through trial-and-error one by one or can it be obtained from crystal datasheet? I have never done this before.

Thanks.

Just discovered the answer myself. Choose the longest startup time.