By all means, Kris, please, please, please stay with UIWebView. Anything *not* using it (apart from whatever iBooks is using) consistently gets into issues with text formatting (which will make Alexander/Faterson *really* unhappy ;-) ) and opens the portal to a dimension of pain for both you and us as your users.
Using the Adobe SDK to support their DRM, btw, would necessitate moving away from UIWebView, too.