I am making a sheet cake next week and am wondering are the Wilton Silicone molds good to buy to use to make fondant letters and numbers?? Or is there another brand better to buy??

Sorry earlier post wasn't explained right by me. 

I recently bought the Wilton ones and liked it just fine for my "Sheppard Trucking" cake.  Sorry I don't know how to post the link but you can find it through my profile and photos.  It depends on the size of letters you are looking for.  I love my fmm cutters, especially the Funky ones which I used on the front of that same cake and many others.  I also have and use the script and block letters by the same company.  You do have to roll the fondant/gumpaste thin and I let mine air dry for about 10 minutes before I begin cutting.  I use Tylose in my fondant to make the paste that works well for me.  Hope that helps.

I HATE the Wilton silicone molds!!! Everything gets stuck in them! I don't know if any other people have had good luck with them, but they're cheap junk. 

Try Tappit letter cutters. You can get upper and lower case. You will LOVE them. I buy mine on Amazon. 

One trick to using them...Roll your fondant really thin! Let it sit to dry for a little while so they are easier to cut and hold their shape. When you cut your letters, roll the cutter around on your surface to get nice sharp edges! Tap the letter out onto your counter and let it sit a little while longer before handling. They will basically be dry when you put them on your cake. If you don't let them sit, they won't hold their shape. 

If you don't have time to order your cutters for next week (Amazon will ship really fast!), get the metal letter cutters from Wilton. I use those often and like them. I just don't like their silicone molds.