My best advice for anyone new to detecting is pick a detector that has the features you need for the type of hunting you will be doing the majority of the time. If your going to be selective in your digging like hunting modern parks and schools for coins a detector with an accurate TID or tone ID is the way to go. If your looking for jewelry along with coins at these same sites you have to dig it all, foil, pull tabs and bottle caps so tone ID and or meter is not needed. I don't think the Advantage would be my pick for selective digging in modern sites. It's more of a dig it all detector. The forte of the Advantage is it's great depth in mineralized ground and iron infested sites. The Advantage loves small foil and aluminum which suites me just fine as it is pretty sensitive to small gold for a low frequency detector. I use my Advantage only in areas like old iron infested ghost towns and beaches where I want to dig everything that beeps. For cherry picking old parks, schools or lawns for old coins only I use one of my detectors that has a meter so I can be selective and not waste time on the modern trash. As far as the old steel bottle caps, all detectors like round things like these caps and rusty washers that have been in the ground for a period of time and these can be a problem. Some detectors handle them better than others but most will still hit them and ID them as coins. Yes guys , even the Sovereigns will hit these rusty caps and washers and like any other detector you have to learn the Sovereign sounds to be able to ignore them. Whether it's a TID or non TID detector some will give you clues in the audio signal that the target might be a rusty round object. On some detectors it very noticeable on others it takes a bit of time in the field with the detector to hear or learn the difference. In my ground with the Advantage these rusted caps do give a repeatable signal but the tone because of the rust is really harsh compared to a good target. It just might be my nasty ground or maybe my ground balance settings as I always manually GB the Advantage for each and every site. One thing you could try is set your discrimination to 10-11 o'clock sensitivity at 1 o'clock take several rusty caps and ground balance your detector to them and see if it might help with the audio ID.