My F75 is a Ma-Ma upgraded model, one of the first sent in (fools rush in). I was happy with it when it came back, nice and quiet, very usable, but then you guys over pond (im in the UK) started with the low grumblings that turned into a roar. I only detect in Discrim' mode but decided to test out AM mode, sure enough no extra depth and the Ma-Ma bug. So emailed Juan who said "send it back and we will fix it", he sent the Fedex details, so i packaged it all up ready for the courier to collect. Then i thought, what about insurance!!. I queried this with Juan who replied "no the package is not covered for loss or damage, but Fedex are very good". Sorry but the F75 has cost me £1000 ($1600) four months ago plus £100 postage to send for the original upgrade, so there was no way i would risk sending it half way around the world uninsured, you would have thought a company the size of Fisher would have negotiated with Fedex an insured option. So i guess i'll have to put up with the Ma-Ma pinpoint which isn't a problem.