I did the cross-promo for both contemporary and the fantasy/paranormal. Great promotion. Both were very successful. When all of the authors chip in and share it in groups, newsletters, websites, their own groups and pages, and comment/like/share on the others’ posts, it really helps.
My fantasy title sold 60 during the promotion and my contemporary title sold 43. I consider that a good sale for only a few days!
I’d definitely do it again.