Well atm I'm not so sure the tech has gotten better. Few bells and whistles with new machines.
I had a 2200d with a 14dd coiltek with booster. Now I've got a 5000 with multiple coils and none of the new coils on the 5000 punch deeper or give a sharper signal than the old 22 when tested on a .5 and .7 nugget at various depths. I tested the 5 on all timings and different adjustments (gains, stabilizers ect) using these coils; 17x13 , 17x11, 12 x 8, 12 round, 20 round all monos. I also tried the 11 commander dd on the 5000. The dd didn't even pick up the nugget at all. Not even a threshold mermer at depth of 5 inches.
All the above tells me the 5000 has way less punch just settings to dull the machine rendering it down as usable , but not practicable :| Dropping to a mid sized dd for mineralization on the 5 is really just saying, Hey I work but you might as well go home.
As for finding gold in my experiences unless you spend 1 day raking an area, using a detector is limiting yourself down to near zero chance of finding yellow. However it gives us prospectors a bad name so I tend advoid raking. Here's the delemer, rake or not :/
In my opinion the gold is still there, but no doubt it's harder to find. Probably under all those leaves :argh:
For me it's like fishing: It's all about the hunt, not the outcome.