Fetching external resources in parallel in node - good practice?

I have a setup where a node server acts as a proxy server to serve images.

For example an image "test1.jpg", the exact same image can be fetched from 3 external sources - lets say -

a. www.abc.com/test1.jpg
b. www.def.com/test1.jpg
c. www.ghi.com/test1.jpg

When the nodejs server gets a request for "test1.jpg" it first gets a list of external URLs from a DB. Now amongst these external resources, at least one is always behind a CDN and is "expected" to respond faster and hence is a preferred source for the image.

My question is what is the correct method to achieve this out of the two below (or if there is any other method)

1. Fire http requests (using mikeal's request client module) for all the URLs at the same time. Get their promise objects and whichever source responds first, send that image back to the user (it can be any of the three sources, not necessarily the preferred source behind the cDN - but doesnt matter since the image is exactly the same). The disadvantage that I see is that for every image we hit 3 sources. Also the promises for http requests can still get fulfilled after the response from the first successful source has been sent out.

2. Fire http requests one at a time starting with the most preferred image, wait for it to fail (i.e. a 404 on the image) and then proceed to the next preferred image. We have lesser number of HTTP requests but more wait time for the user.

Some pseudo code

Method 1

while(imagePreferences.length > 0) {
   var url = imagePreferences.splice(0,1);
   getImage(url).then(function() {
        sendImage();
   }, function(err) {
        console.log(err);
   });
}

Method 2

if(imageUrls.length > 0) {
    var url = imageUrls.splice(0,1);
    getImage(url).then(function(imageResp) {
        sendImageResp();
    }, function(err) {
        getNextImage(); //recurse over this
    });
 }

This is just pseudo code. I am new to nodejs. Any help/views would be appreciated.