In addition to quilting, my studio is used for my oil painting. Therefore, the walls are as white as I can get them, and I have 6 full-spectrum fluorescent light fixtures on the ceiling with one above each of three workstations - and NO WINDOWS. With this setup, the colors of fabric and paint stay the same 24 hrs a day through every season. These old eyes need all the help they can get! Even without sunny windows, the music is divine!
From everybody's comment, it comes down to personal choice, and what environment you want.