Shoes...shoes...shoes

I let my girls chose their shoes, I just dictated the color. I never liked it when I was told what shoes to wear as not all shoes are comfortable and there is nothing worse than walking all night in shoes that hurt. If your dresses are long, shoes won't be seen anyways. If your dresses are short and you want the shoes to match, maybe see what $20-$30 shoes they would pick as maybe you would like them and then everyone would be happy. Even if you plan on purchasing the shoes for them you still want them to be comfortable in the shoes.

I would let them pick their own. Some people have a hard time finding shoes that fit their feet well and you want your girls to be comfortable.

Are they all okay with the requirement of silver colour and a 3 or 4 inch heel? Will they have an alternative to change into flats or something after the ceremony/pics?

I wouldn't order the shoes for them because (as my MOH pointed out to me) if YOU order them and you're just going off the size your girl's tell you without them trying them on, they may end up too big or too small, shoe sizes are tricky to pin down, I'd let them pick as long as it matches similar to what you want..

I'm letting my girls pick whatever shoes they want as long as they are silver, but that's because my dresses are long. If my dresses were short I would definitely be picking since everyone would see them. Are your dresses short or long?

Dresses are a high-low style so the shoes will be seen. I'd just like them to match. I told them I didn't care about how high of a heel they wanted as long as we could pick the same shoe for everyone. I personally like shoes to match when they're going to be seen. Also I mentioned about getting a flat to change into after the ceremony and pictures are finished.