[quote name='Roufuss']
Finally got all 32 Fast Staff unlocks, and got the unlockable!!!
Rainbow Road was a bitch, it took me an hour to get my time from 3:02 to 2:56, phew! The rest were easy with the bikes, except that damn Yoshi Falls

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Based on my little bit of play time, I still feel like karts don't stand a chance against bikes for time trials. I've only been able to time trial enough to unlock somewhere between 16 to 24 fast staff ghosts and even beat a few. (I wish I had more time to play--the release came at a bad time.)
If anybody wants to know the easy way to unlock staff ghosts to get unlockables, use the Bullet Bill bike set on automatic. It makes things so easy that you have to force yourself to go back to manual.
Once I'd gotten used to bikes from trialing, on a lark I went into the first two 150cc cups for the first time and immediately one starred both. Opponents never got within 3 seconds of me in any race, and it wasn't me as much as it was the bike. Yeah, I knew the tracks a bit from time trialing and 50cc, but outside of that the bike did the work. One thing that makes it easy is that, with a few exceptions, people running into you with heavier bikes or karts rarely harms you.
I need to look online to see what people are doing with karts, but I think if you get the hang of wheelies, wheelie cancels, and learn the tracks, a bike is tough to beat. Maybe too tough, IMO, seeing as how it's Mario KART.