^^^
Recently switched to a DD and I agree its badass! Having said that I'll be putting the Painkiller back in that guitar. Its just everything the DD is but faster tracking, tighter, more defined, and with more punch to palm mutes and single notes.
I find the eq of the two very similar. The DD may have a tad more in the low mids, but the PK gets the nod in the low end department. Both have ripping upper mids, but the PK's are more open and crunchy compared to the compressed nature of the DD. I find the highs more pleasing with the DD which is probably attributed to the compression vs. the more open nature of the PK.
There are definite advantages with the DD for me such as the amount of compression which makes it a bit more forgiving. The PK can be so damn unforgiving because of its articulation, but the clarity, aggression and balls that bridge is capable of are addictive. If you have the chops, its AMAZING for all things metal.
All just my personal experience of course.