My SIL wants me to make this cake for her wedding. She wants it to be only 3 tiers and wants it to serve 100 guests. I have showed her the different serving sizes and she wants to go with the 1x2x4 inch serving size. My question is.....well I have a few questions really
What sizes would you suggest making each tier??
6inch, 8inch & 10 inch would serve exactly 100 (and no she does not want to save the top tier) but would the sizes look good for this cake??? What do you think???
Also do you think I should stack the tiers directly on top of each other?? and put the roses around the border?? Would I need more than a 2in difference in tiers if I did it this way? Or should I use the hidden pillars and have a 2in space in between the tiers in which to tuck the roses in??

I agree do the hidden pillars and tuck in t he roses. It will be beautiful done this way and she will be pleased.

Yes, the 6, 8, 10 would give you exactly 100 servings using sq cakes. It won't give you much room for the flowers - especially if you make them as big as shown!
<...Or should I use the hidden pillars and have a 2in space in between the tiers in which to tuck the roses in??...>
Sounds like a good idea to me. W/the sizes so close you might have a problem w/'hidden pillars' as they are wider than pillars. I'm concerned they might tear the cake being so close to the corners.
Maybe someone like IndiDebi has those sizes on hand and can tell you......
Ooohhhhh I just thought of what I would do.... use
round plates w/the sq cakes. If each cake is on a cake board the same size of the cake the board can be covered w/the ribbon and then the pillars would be in a bit more from the edge/corner.
If a 10" sq cake is placed on an 8" round plate it would be just fine.

This cake is a 6/8/10/14 (so cover the bottom tier and it will give you a good visual): http://www.cakecentral.com/modules.php?name=gallery&file=displayimage&pid=1153773

This one is a 6/8/10/12 with a 16" styrofoam. I used hidden pillars on this one. It was back in october and I don't recall any problem with the hidden pillars being too close to the edges, but it's a very good point and the suggestion of using round plates to move the pillars in a bit is a good one. http://www.cakecentral.com/modules.php?name=gallery&file=displayimage&pid=1119353

Thanks so much for all the great advice! I have a few months until the wedding so I am definitely going to do a practice run first (this is my first wedding and 3 tier cake).
Thanks again!