I have and have used the 9x12 for over a year now. I have 2 250s one with stock coil and the other with the 9x12 coil. A little trick I use is to clean the area with the stock coil digging everything. Then I hit it again with the 9x12. Some of my best finds have come this way. W/o trash to mask signals and in a damp to wet soil I think I can get 4 inches deeper, but I've never really measured it or anything, besides who's got the time to pull out a tape measure when we think we've found a really deep item ? I just wanna close up that hole and move on to the next find.
Since this tread appears to be over, let me hijack it....what all have you found by doing what you said using the stock coil first, then the larger one

? sounds like an interesting idea...I would like to know what the air test difference in depth is......Thanks, Tom
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