You have 15 mountains in the distance?  Are you planning on doing this in landscape orientation?

Why not make 2 or 3 of the terrains larger and cut down on your polys?  You can vary the terrains by using the y-rotation so they don't all look the same but you'll have a lot fewer polys to deal with.  Then use the same material on each of the terrains.

If you look at some of the sample images on the content disk you'll see that they only use a few terrains for distance, even when trying to create a mountain range.

Hugz from Phoenix, USA

Victoria

Remember, sometimes the dragon wins. Correction: MOST times.