Directly anyone starts to lose an arguement they move the goalposts. No one ever said Tesoro detectors are toys just that they are lagging behind. They fell behind several years back and Arizona Al who was a dealer for Tesoro warned of what was happening with just a few slight tweaks to the latest designs. Don't know if his words had any effect but they did follow up with new models the next year.
Now to get down to facts. Tesoro has not improved its pulse as just about every other pulse manufacturer has, it has gone backwards in hardwiring the coils (Detector Pro improved hardwear, C-Scope, lighter, cheap and a processor, Whites with ground balancing models and the DF coils plus gain and pulse delay controls on the D.F., rather than just one or the other, hoard hunting models have been improved and the coil ranges extended to allow searching for individual coins not just large objects, plus pulse discrimination by hybrid designs or the addition of magnetometer coils). Most manufacturers have worked to reduce pulse delay times because for a sensitive P.I. you need the ability to be able to turn off the current pulse as soon as possible to induce a high voltage spike (can be as much as 400 volts) and then get back as near to zero volts in just a few microseconds.
As for the general range of detectors, recovery speed is why people bought the XP Goldmaxx, Power and now the Deus which are all rather expensive machines. If they wanted an American brand in the past they would pick certain Compass models and today a Gold Bug SE Pro, Teknetics T2 or G2.
Lag behind and you lose sales. When I met up with Jack Gifford, who would come over to detect with Frank Mellish, his importer, every few years just about everyone had a Tesoro for plough soil detecting. Twenty years on and you see a fraction of the amount in use. Doubt if I could buy a Sand Shark except by special order because the sales are just not there for a dealer.
As for my working for a manufacturer or being a dealer unfortunately not, though Garrett users suggest I work for Minelab, Minelab for Fisher etc. I detect for a living and to do that you need to use the best, not one brand whatever it is.