Background of the front cover

I wanted to now look at whether or not to keep the cover background white or change the background like some front covers do.
I tryed a few backgrounds out, I narrowed it down to 3:
a plain white background

A grey background

and a slightly greenish background:

In order to decide I put them all on one document to help me compare them easier:

Looking at them all together I think I like the plain white background the best, I think the cover star stands out the most with this background as the grey especially is too dark. It is important the coverstar is the centre of the cover and is one of the first things the reader notices as my target audience research shows that the coverstar is the main thing that influences them to buy a magazine. Although I do like the green/yellow background as it is slightly different, looking at other magazines they usually stick to a block colour for the background.