A friend of mine is getting married tomorrow and I told her that I'd help her out with the cake... She baked it and made white chocolate leaves for decorating, all she wanted me to do was to frost it.
I've done poured fondant on small cakes, but not on large tiered cakes... and I'm thinking that buttercream might be simpler! She's not picky about it, but I just don't want to screw it up as I don't have the pans that she used (flower/petal shaped).
What should I do? Experiment and use the poured fondant, or stick with the old faithful buttercream?
TIA!

That's two totally different looks, I'm not sure if I were you I would want to experiment this late in the game. I think the white leaves and the paleness of the poured fondant (you didn't mention any color) might look strange. I would stick with buttercream

Jibbies

I wouldn't recommend doing poured fondant. You'll be able to see the cake through it, which is fine for petit fours, but may not be so great for a wedding cake.

The best way to ice the petal shaped cakes is to use the cake icer tip. Just go around a couple of times to cover, then gently smooth with Viva.