Well its horses for courses. I have had many detectors since 1977 43 years ago. The Whites v3i i have had since release 2009 updated from the v3 to v3i. Now if you coin & jewellery with correllate with span at 1 and use frequency offset going up and down the scale from -5 through to =5 this is your fine tuning. You will find that at 1 you will be able to get some fine gold rings but no foil or pulltabs or aluminium .The way i use it is set it up -2 through to = 19 this is my first program with discrim accepted to =22 the tones accepted to 19 with the rest blocked out. Sensitivity set so you are just at grass root depth. As you increase you spam and frequency offset you will have more rings and this will also start to bring in foil aluminium etc. If you are searching for gold chains best data is your go. I Have polar plot with a graph on the screen which tells me where foil is sitting and other targets. Recovery delay is also very important & resolution you will get a lot more about your target with resolution set at 1 using 3 frequencies. One other thing is to come down to a smaller coil i use the 7 inch mars dd it is incredible in sensitivity. After gridding a patch with string lines accross the grass i then go over the same area again with my second program for the larger gold rings. The v3i is an incredible detector and it does take some time to master but when you get the gist of what to put with what and you save it you only have to do some minor settings to suit the area of new ground you are going to search.
Try doing this with an Equinox 800 and you have not got a hope you can do it but you will be digging a heap more junk.