Personally I like machines that have modulated audio, this is critical for me to hear the deeper targets and know their size. I often hunt with the Tesoro or if one my other machines that have saturated audio I will switch to all metal mode and use vco.
What I don't like about many of the new machines is the large DD coil as they are very unproductive in my neck of the woods. Other thing I dislike is the menu systems. Digging through menu's looking for settings and fiddling with them to try to refine the machine for a particular situation is time lost hunting. Nokta did a great job on the Anfibio and Kruzer series with their menu clearly layed out with slew of features then came along the Simplex with a Nox Lite look then the Legend that has been patched over and over for features asked by users after the fact.
I don't critisize people for what machine they use nor to I shame them. I'm not a label wearer and more focused on what works for me. One of the biggest turn offs for me on forums is when someone boasts the latest machine and the find they got as if that was the only reason they found the target. Other thing I despise is when people who test the machines for a company and recieved the unit free from the company go and boast about it and over sell it's capabilities.
As I have said before the coil choice is more critical to success. Many of features the companies add are more for selling units than are actually necessary if the machine was properly designed and programmed in the first place. This can cause people to fiddle and miss targets (which is a good thing for me). With all the features they have on SMF's where is iSat and why don't they have a true all metal? Why have weighting on frequency ranges when the point is to have equal sensitivity across a range of conductors?
As for deep targets majority of targets are in the 10" or less range. This is the active range for earth worms and the main reason for targets to sink. Why more often than not larger targets with larger surface area and weight are pushed deeper than tiny lighter coins. There are cases where ground was dug up such as foundations or where tractors had pushed the targets down in the mud but with minteralization and in case of foundations there are too many junk targets above to get any substantial depth no matter what machine you use and large coils will just make things worse.