I want to go nugget shooting once a year, beach combing once a year, and the rest of the time I want to coin and relic hunt. What model of instrument should I be looking at?
A general purpose would give you the best all around performance. Only when beach or prospecting consumes the majority of your search time would it be wise to look at a model specifically for that purpose. Although prospecting or beach models offer increased performance for their purpose, they are not as effective as a general purpose models for coin and relic hunting.