Interesting comments from all, thanks for the feedback.
BlueDreamer: testing is a good idea, getting both passed will be difficult.
Nillervision: they're front page banners, if you take a look at a site like say : https://www.hollandandbarrett.com/
you'll see they use a black BG, and alternate images pretty regularly. That's the idea here, rotate images on say a fortnightly basis to promote diff products to new and return visitors.
davep: this would be the primary banner top of page, just beneath nav menu. Spot on with the print design comment.
fisicx: yeah, you're right on possibly needing new designers, not sure I agree on never use a black bg, seems to be trending now days, see for example https://www.hollandandbarrett.com/
that's pretty similar to the layout of our site. Def needs a buy now button, was looking for feed back on impact, which would likely garner more clicks, which looks better etc.