Hi Colt,
I don't have a GS 2 but have a GS 4, so I suspect it would work ok but it will have some quirks like typical drift and the putt putt sound.
Looking at the controls, it appears to be very much like the GS 4, since it has about the same controls but the box is much larger than that of the GS 4.
Now, with that said, if it doesn't come with the instructions, you might search for the GS 4 instructions since I suspect they will basically apply. If you can't find a copy, I might be able to find mine I have in software for the GS 4. I also think I posted the instructions on the Geotech forum so you might find them there also.
Just out of curiosity, did you buy this unit and was the price reasonable?
Getting back to the detector, assuming the controls respond basically the same as on the GS 4, this detector has a built in feature you might like and that is, you can hunt trashy areas in the select 1 mode and ignore most nails or other thicker ferrous trash and still detect most gold nuggets one might find in the field today. By this I mean, the Sel 1 mode fundamentally ignores larger targets or targets one might consider high conductor objects. This includes the larger nails and other iron junk mentioned before, but also includes silver and copper coins, very solid relatively pure gold nuggets greater than maybe 1/4 oz or so.
What will be detected will be smaller gold nuggets, less than 1/4 oz, many larger gold nuggets with lower purity or very rough in character, small pieces of tin cans, boot tacks, or smaller nails or pieces of nails. Also, many non ferrous objects such as bullets and casings, brass and lead objects or other lower conductive materials will also sound off.
You will find that the ground balance control does determine just what is ignored or detected over a limited range.
This unique feature basically functions the same as the low conductor mode on the TDI except the audio is different.
What would be nice is if you could find someone to add a couple of resistors to add the autotune feature. Right now, the reset button most likely resets the threshold level.
The foil reject feature is that same as the delay on Eric's newer designs, so when hunting for small gold, keep this control at minimum which is the shortest delay. The shorter the delay, the more sensitive the detector is to all objects but very noticeable on small gold.
I hope this helps a little.
On a little different note, with the prices of used TDI's coming down, I would need a nice low price before I would buy it.
Reg