Comparing 550D DNG files to HDR capture, I get better frame rate in HDR mode (@1/2fps of record setting) compared to 2fps for DNG

. And a similar dynamic range. But it's not all good news for HDR as the RAW capture has much more sharpness and better color rendition. However, while the frame ratio is taller in DNG recording there are fewer lines available to record. So there seems to be more moire effects(?).
And much more noise in the DNGs which I found difficult to remove in post (even at 100iso). Shame I can't have just a bit more detail in the h264 file.
Here is a screeny comparing the result of HDR merge of 2 frames and a RAW DNG:
http://imgur.com/mCQ2LyF