I am doing a TT, and I am not sure if I need to use a crusting BC or can I use a non crusting BC?? I know not to use a whip cream because of the sliding issue. What is best to use??

I have done 2 of them recently - both in crusting buttercream. I just ice and smooth each layer before stacking - just make sure you cut the hole large enough for the next layer to fit down into!

Here is a pic of the first one I did:

http://www.cakecentral.com/modules.php?name=gallery&file=displayimage&pid=1357281

Thanks Loucinda....any other suggestions out there?

I just wanted to say if you want to have the "sharp" edges on the cakes - the best medium to do them in is fondant. I didn't want those edges on mine, so it wasn't a big deal to me.