Hi Dan,
It does sound like Account-Based Marketing is right up your alley and Im happy to see your looking into personalization, which is a key enabler for ABM. Marketo Real-Time Persoanlization can easily integrate with SiteCore (and for that matter, any CMS) without requiring any coding or API calls which you will need to use when working with DemandBase. We also integrate with Marketo Marketing Automation and can even leverage lead data such as score, title and more for individual based marketing, the only solution that can do that, creating meaningful 1:1 conversations with individual decision makers within targeted organizations.
A few other differentiators between us and DB are that we automatically discover content on your site and emasure its performance. You can choose to enable our preedictive analytics-based content recommendation engine which basically does for content what Amazon does with product recommendations.
Since DemandBase is simply a database with API's you can use you will need lots of coding and customization work for each campaign and each page you want it on. With RTP you need zero coding, our smart tag learns the structure of the page and you can use our segment/campaign wizard to define your targets (industry, company, product interest, specific behavior, location, etc.) and the content they should see (banners, video, text, image, call to action, etc.).
With DemandBase you can only target firmographics (company, vertical, etc) while with RTP you do that AND correlate actual behavior and intent.
As for pricing, lets just say you'll find our a lot more "friendly".
This is just a short recap of the differences, lmk if you have any more questions.
Thanks
Mike