As email marketers, we never know what mindset email recipients will be in at any given time. So a good idea is to design your copy and creative to speak to all personality types/buying modalities: competitive, spontaneous, methodical and humanistic. If this makes you go "hmmm?" make sure you check out our explanation of the buying modes in our personas webinar and webinar recap.
I've been a big fan of Crutchfield's marketing for a long time - I consider them to be one of the top retailers in that regard. Here's a perfect example of why: Crutchfield recently ran this email incorporating ratings and reviews (an effective and underused tactic for retail email), and includes content that speaks to various buying modes effectively.