With his initiative, his abilities and a power weapon you can expect the banshees to cause so much pain and discomfort in the heavy armored infantry of the enemy, the only issue is their low strenght, which can be compensated by powers from a supporting farseer or adding jain zar to the squad, but the latter solution is a bit pricy.
The case is that the banshees are usually painted in brownish colours, but I prefer my banshees to fit a bit more with the "ghostly" look that the aspect name implies, so I painted them white with clothes and crest in blue, which I think gives them the proper phantasmal look although a bit dirty.
Here they are.
Here you can see the crest and tabard colours.
A pair of banshees.
The swords are painted metallic and heavy washed with asurmen blue.