Snell Type E/III or E/IV?

I've heard the E/III's before and they were very good sounding speakers for the price, especially at the prices they are going for used now. How do the E/IV's compare? I notice from Snell's website that the E/IV's are a little taller and narrower. Also, the rear tweeter is 1" instead of 3/4". Has anyone had a chance to hear both of these E models?

Thanks for any input.

Scott