As far as depth goes, on land it is probably one of the deepest detectors out there in all metal mode with a slight threshold. 10" dimes in my mild ground are no problem. If you are a dig it all guy the Tiger is great. If you want to use disc, it is another story. The disc circuit is not like your normal land machine disc. It is very hard to disc. out a pulltab without turning the disc. almost all the way up. Doing so you will loose some depth. In the water the disc. is usually set around 2 to get rid of most nails and small iron. This detector is extremely sensitive so on land you would have turn the disc up to the point you could tolerate the amount of digging you want to do. The Tiger loves bottle caps and they can be hard to disc out also. This is probably the best VLF detector you can get for freshwater, NOT saltwater. I was in your shoes this spring and purchased the Tiger for water and figured I would use it for land also. I ended up buying a Silver uMax to do the land work. I like to land hunt with disc. turned up to eliminate most trash and concentrate on silver and the clad that comes with it. Ther is really no water detector that also makes a great land detector. In the long run you are better off with a dedicated water detector and a dedicated land detector. You can get a Silver uMax for land for about $250 or a Compadre for $160.
All that being said, my friend uses his Tiger on land all the time. He digs it all and has made some really great finds. In reality you don't dig it all as the tone can usually give an indication that the target is not round like a coin. Odd shaped items get raspy at the begining or end of the tone. A coin or ring or something nice and round will give a clean signal from two swing directions that are nintey degrees from each other. This would include bottlecaps. Tesoro makes a hip mount pouch for the detector box so that is much lighter to swing. It would be considered heavy for a land machine.
Can it be used for both? Yes, it can but in my book it is not ideal. I will say though that if I ever wanted to dig everything deep with no disc, the Tiger in all metal mode would be my choice.
One thing for sure though, as far as a freshwater detector the Tiger is one incredible detector.
