you will always get this problem , no matter what format you use. What I tend to do is decide on my own internal structure for verticies, normals , tex coordinates and convert the file format to that when loading the file, it might be a little more extra work, but because you've decided on your structure you can use the most optimal method to render it.

I use glVertexPointer, glTexCoordPointer rather than interlieved arrays and I make sure all the models I use can converted in to my structure when loaded.

I hope this helps?