I have used the Tesoro 10X12 coil on my Vaq and I love it.
For hunting large areas and covering ground efficiently it works better than good.
I never get the feeling I am missing much at all when I use it.
Depth is great and sensitivity is not quite as good as when using the small snipers which seem to pick up the micro stuff better, but for normal sized coin and jewelry targets it has no problems.
Last fall at a special site our club was hunting this set up found me my best and oldest coin ever in an area that I saw at least 5 other club members search with all different kinds of detectors and coils.
This beautiful 1865 2 cent coin that came in loud and clear and solid as as any coin I have ever found...I have no clue how the others missed it but I don't think most of them were using DD coils.
Another time near the end of a long hunt with not much great to show for it except some modern clad I was in a park literally running around swinging so fast and wide you would have laughed at me, but I was looking for just one more "Hail Mary" good signal so I could go home with something great and luckily it happened.
Due to to speed of the Vaq and that wide coil I did hear a quick solid tone even at that to fast swing speed and stopped and went back to examine this signal further.
In the same hole as a beaver tail tab was also this nice 14k woman's wedding ring and even at melt that ring paid for the coil easily.
The only thing I don't like about this coil is when using concentrics those high tone pop tops will usually disc out and I can avoid most of them with confidence, but using DD's they usually come in and mimic dimes and quarters a little too well but I deal with it if I happen across an area with lots of these.
Not sure how the SEF coil would differ, but in my good soil here in Kansas I couldn't ask any more of the Tesoro coil than it already delivers.
I get very little noise and no more noise using this coil than the standard or 5" concentrics that I also own probably due to the sensitivity and ground balance adjustment ability on the Vaq.