Hello Darryl,
I can understand your hesitation with getting the AT Pro, Some of the users have been having problems but Garrett will follow through and take care of the issues.
I have an AT-Pro, One from the first batch and sent it in for the coil replacement. It works wonderful and is waterproof, No leaks from the headphone or coil connector or face panel it is waterproof.
On land it does detect deep, Very good for land gold jewelry detecting or coin shooting a fun machine to use for sure. For fresh water it does well, Better than most VLF detectors but it does suffer masking from the fresh water lakes and rivers with black sand, You won't get depth under these conditions but it will operate smooth getting the shallow targets including small signals with ease. A considerable amount of depth will be lost due to the masking which is common for our area, You may be under the same hunting conditions we have with you only being 60-80 miles west from our foot hill area.
Being a serious water hunter you should try out the AT Pro, No it won't detect deep in fresh water with harsh soil conditions but it will operate smooth yet get decent depth allowing you to get the smaller gold jewelry finds.
(Stock DD coil) Recently, Came across Goldtooth at a local water spot, He was using a waterproof Tesoro Tiger I believe, We compared our machines on a thin gold chain he uses for testing and his Tesoro hit it strong, The AT- Pro hit it too but I believe had I been using the AT-Pro 6.5 X9" coil it would have had a stronger signal. Since then have ordered the 6.5 X9" coil but have not tried it in the water yet, I'm hoping the 6.5 X9"coil will reduce masking from the harsh soil we endure and enhance the smaller signals as well.
(Pi detectors) Of course they go deeper than the AT-Pro in harsh conditions, I have an Infinium and it does extremely well with no masking effect from these harsh lakes in our area. But if you want to cherry pick a spot then the AT-Pro will suit your needs, Both visual and audio ID in a waterproof detector.
Anyway, Don't hesitate and get an AT-Pro with the waterproof headset. I think you'll like it allot, Use the Pro custom mode and in harsh soil don't be afraid to reduce the sensitivity due to masking the AT-Pro still gets decent depth using minimum sens.
Paul