I pulled my 2007 Epi catalogue and the from that book, the Dot Studio and the G400 have the same pickups. The Dot Studio has the open coils. I measured my 2007 G400 using the patch cord/multi meter system, and found the pickups to be 8.21 Neck and 12.95 bridge, resistance. I would expect the open coils to be hotter. I also have a Sheraton II that is just a regular Dot with a lot more bling. That one has the stock epi pickups from 2001 and they are at 8.43 and 8.67. This of course is a solid block guitar so very little feedback. I like these pickups because it gives a kind of dirty mellow tone for the blues.
My ES335 has PAFs in it and they are in the 7.11 and 8.79 range. Again a centre block guitar not full hollow body.
What I am getting at is that if you like the tone of the stock pickups you would be looking at a set of Gibson 490/498 pickups or something aftermarket like that.
If you want a little mellower tone but still some bite, as Spudman said, I would go with a PAF or PAF clone.
That being said I hope you realize that if you do go with the pricier pickups you will not recoup that money if you sell. Also get wqx potted to keep the feedback down.
Another option is to change the pots and caps, which usually opens the stock pickups up a lot. On a Dot that would entail a lot of fishing and I am not sure I would tackle that one on my own. I have found by comparison that the newer off shore stock pickups are much better and fairly close to the originals.