As far as the fisher gold strike goes, I have and use one. It finds gold as well as most other detectors, but has some throw backs that made it unpopular. The biggest complaint was that the learning curve to get it to operate effectively is much more difficult than most detectors on the market. Fisher wanted a MD with all the bells and whistles (as compaired to the gold bug series) and went, in my opinion, a little too far. The control panel is difficult to read unless in good light... red lettering on black...
Overall If you take the time to learn how to adjust it correctly (and that means correctly for whichever ground conditions you are in at the time) the gold strike works well. I would not recommend it to anyone just starting out but to someone that knows the difference between discrimination and sensitivity and generally knows a lot about how a detector works.. It can be mastered.
I have found nuggets large and small at depths of from the surface to 8 or 9 inches deep. The auto ground balance, and tracking work as advertised, and the recovery of nuggets in a field of hot rocks is quite good. The Gold Strike is much noisier than say the Gold bug II or similar detectors but when (or if ) you get it right it does at least as well as most top of the line VLF detectors.
The learning curve is most of the problem... you have to try it out in a test garden and practice, practice, practice. Once you learn to adjust it right it will do you a good job, but learning to adjust it right isn't easy.