Classic series, and competitor's models such as Tesoro's discriminators, often tend to be annoyed with any model that has a delayed response, such as most Garrett's, Bounty Hunter's, and the Prizm series (other than the 6T) to name a few. I even add my name to that group ... IF I am considering what I class as a "top-end" or "high-use" unit for me and my needs.
It is also a price-point issue when I am looking for or suggesting n affordable detector for newcomers to the hobby on a tight budget or for their kids. Keep in mind, however, that many hobbyists have been making do with a garret or Bounty Hunter or some other model that they might have started with that also has a delayed response and, to them, they don't know there is a difference in some detector performance designs. I know many people who bought a Prizm model when they got started and liked it. They hadn't used something like an M6 or IDX Pro to know there was a difference in response/recovery speeds, and they were shopping within their budget.
I felt the Prizm series didn't match what performance I have been enjoying from the Classic series that is essentially replaced. For the dollar investment, it was fine for some others, but not for me. The exceptions are the 6T and the new Coinmaster, which is a bargain Prizm with a good old name. The 6T has a quick response, auto-tracking Ground Balance, and the only way it compares with the rest of the Prizm line-up is that it uses the same control housing, same search coils, and operates in the same frequency range. That's it.
The new Coinmaster takes the bite out of the price and is, in my opinion for what it's worth, exactly what I wish the Prizm's would have offered and been priced at from the get-go! If it were me, I'd trim the arm strap and rod lock off another model and drop the price and limit the Prizm series to two models. The Coinmaster and Coinmaster 2 or II or Ltd. or "T" (for Tone ID) or ???? I'd keep the 6T, but drop the price at least $100 off the suggested retail as it crowds the M6 in that range.
I think it has mainly been the price point that has turned some away from the Prizm series, or that the competition offers something similar for less from the start. They are good detectors, but I think many (most??) of those who have purchased a Prizm model are not the ones who are quite active and visit/participate much on the forums. Due to this we just don't see the input from Prizm users as much as the upper-mid or high-end models.
Monte