In an old thread on this subject I dug up numerous links that support the idea that sliding into first slows you down, but I am not going to dig them up again. To me, it's common sense. Running through the first base bag will be faster than sliding, every time. The only time one should slide into first is if the first baseman has come off the bag, and is trying to apply a tag. A person may feel sliding is faster, but it simply isn't. And yeah, it's more dangerous as well. Didn't Mythbusters cover this as well? I'm pretty sure they did, and running through the base was much faster. They aren't athletes, but the evidence was still there. The Mythbusters tested sliding into a base versus stopping directly at the base (not running through it), which seems like a huge waste of time to me.