Tx for answering my question. as to your question: the problem with the tesoro's is that the factory used to concentrate more on discrimination than on depth. now that they "beefed up" the power, they seem to get better depth on mildly mineralised soil but tend to get unstable, thus forcing you to use less sensitivity. I wonder if anyone was looking for that solution, since in Europe, most interesting sites contain a lot of mineralisation caused by both iron particles, bur also by composted garbage etc, thrown on the land for centuries. BTW: the newer tesoros have one more questionable improved ability: they are so extremely sensitive that you dig all kinds of super small pieces of lead. the older tesoros were also the preferred MD because of its good disc and ability to cope with mineralisation. the older fishers (like the 1266) were not used often on these sites because of the loss of depth and the "poorer" disc. from what i understand, the 1270 and 1236 should be better in coping the mineralisation nowadays, thus making them worth a try over here. on the other hand: i do not feel like digging deep iron, which i do now with the cibola. anyway, your answer seems to lead me to to the conclusions to buy a 1270 (BTW: i have used a 1266 for a few days at a roman site, and apart from the problems it had with all the rusted roman nails i did find a very nice roman brooch then).