Hi Silenthunter
The best thing that you can do is find a metal detecting club in your area and talk to some of the members about what they are hunting for and what kind of detector that they are using.
You will find a lot of people using all kinds of different detectors and all of them will be more than happy to show you what their machine has found. I am not brand loyal and own several different detectors, each used for specific hunting conditions.
To best answer your question, yes you can find good things with your RS detector, I have had three 3300's that has done quite well for me. I know of one guy that has a 15 year old detector and it is amazing the amount of items that he has found, only because he checks every signal. I myself prefer to go thru and only dig the signals that I think are good repeat signals, hey his style works for him and my style works for me.
Using ground is adjusting the ground balance to a point where there is no change when raising and lowering the coil to the ground, in a way it is adjusting the search coil to where it is netural with the soil minerialization. All other objects in the soil will give a signal, proper ground balance means more depth and better target seperation.
Discrimination on most detectors is the acceptance or rejection of targets other than the soil. With little or no discrimination you are hearing all targets in the soil, all metal as it is called, sometimes that can be a bit much, so by increasing discrimination you can reject unwanted targets and accept desirable targets. The only problem with using discrimination is that when you adjust your detector to rejuct pull tabs and bottle caps, you will also loose gold and jewelry. I have found thousands of coins and ten times that much in trash, but that is part of the hunt.
Sensitivity is like the power regulator, on most detectors the higher the power, the deeper you will be able to detect. The problem is you do not want to use more power than the soil conditions will allow, or you will loose depth and have poor target seperation. The trick is to use a much power as possible for the soil conditions of the area that you are hunting, with out over doing it. Each site requires different settings for SENS, as you are hunting try increasing and decreasing the sens to see what effect it has on targets. Lay a coin on top of the ground and notice the difference in distance from the coil where the coin causes a signal as you adjust the sens settings.
Hope this helps
colt