as a couple of 4X6 BlueMax Shooter coils for use with a Classic ID, IDX Pro, 6000 Di Pro SL, XL Pro and XLT. I also used a 'Shooter' prototype on a Prizm 6T.
Due to the DD and elliptical design, they could separate OK, IF swept across two targets positioned left-to-right of each other. Due to the coils length, you still can get masking if targets are positioned close in a front-to-rear relationship.
I am referring to the depth of detection and responsiveness (sensitivity potential) which was terrible. A friend had a 4X6 BlueMax for her Classic ID and XLT that I also borrowed and compared side-by-side with my 4" Snooper coil (BlueMax 350) and the round 4" coil easily was the better performer. Better depth, responsiveness, and all-around performance.
The Shooter coils designed for the other model series all worked much, much better. I've favored a 4" round concentric from White's for the 6.59 kHz models because they work well, and even though the Shooter coils work better on the M6 and MXT's I've had, I like the 5" DD Excelerator a bit better when hunting nails and other small iron littered sites.
Monte