I haven't upgraded yet but I don't think they will do anything that will make it more stable than it is in the stock "coins" program.
Next time find a target at medium depth but a good audio hit even if the numbers jump. Then try the three single frequencies with an offfset of +2. Usually 7.5 normalalized, best data, offset=2 will give you the most stable TID. Next, using your regular swing speed, run through the ground filter settings and set it where you get the best audio, then you might tweak the response. It like it around 50, you'll get good seperation and depth at 50. At 40 you'll get a faster response and better seperation, at 80+ you'll gain depth but lose seperation but the tone will be longer to help if the targets are deep. It will reset about as fast as an F75 with the response set on 40.
Of course get a good GB first and i'd set it on Locktrac before you make the other adjustments. If you leave it on Locktrac just check the GB every 15 minutes or so or if you move to another area.
You'll find that those things will help you, especially the 7.5 single frequency... even though it will seem like you are wasting a lot of the V3's functions... what really matters is getting a good audio, a good TID, and finding good targets. I struggle with that though. I like being able to use three frequencies and I like the analize screen but usually 7.5 simply works better and matching the ground filter and response to #1 your swing speed and #2 the site will help you.
Don't be afraid to lower the disc sens well below what you think should work. I have a friend who runs disc sens on 20 and the RX between 12 and 15 and he has no trouble finding coins at 9"... but it may depend on your soil mineralization. If you have medium to high minerals you may do better with the D2, 4x6, or SEF 6x6... if you hunt in inert soil like FL sand you'll probably do better with the 950 or 5.3 but many people really like the 5.3 everywhere. I prefer DD coils where I hunt.
Remember if you tweak things and the machine gets aggrivating you can always restore from the library back to stock, sometimes this really helps. Remember, don't be afraid to lower the disc sens or the RX gain. Around here I can rarely run my RX above 4 in any stock program.
HH,
Julien